61131420 has 216 divisors, whose sum is σ = 224078400. Its totient is φ = 13434624.

The previous prime is 61131383. The next prime is 61131461. The reversal of 61131420 is 2413116.

It is a happy number.

61131420 is a `hidden beast` number, since 611 + 31 + 4 + 20 = 666.

61131420 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×61131420² = 7474101022432800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 61131393 and 61131402.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 255661 + ... + 255899.

It is an arithmetic number, because the mean of its divisors is an integer number (1037400).

Almost surely, 2^61131420 is an apocalyptic number.

61131420 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61131420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112039200).

61131420 is an abundant number, since it is smaller than the sum of its proper divisors (162946980).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61131420 is a wasteful number, since it uses less digits than its factorization.

61131420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 297 (or 285 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 61131420 is about 7818.6584527015. The cubic root of 61131420 is about 393.9322119628.

Adding to 61131420 its reverse (2413116), we get a palindrome (63544536).

The spelling of 61131420 in words is "sixty-one million, one hundred thirty-one thousand, four hundred twenty".