61017840 has 320 divisors, whose sum is σ = 236234880. Its totient is φ = 14376960.

The previous prime is 61017833. The next prime is 61017851. The reversal of 61017840 is 4871016.

It is a happy number.

61017840 is a `hidden beast` number, since 610 + 1 + 7 + 8 + 40 = 666.

61017840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

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 63 ways as a sum of consecutive naturals, for example, 1151254 + ... + 1151306.

It is an arithmetic number, because the mean of its divisors is an integer number (738234).

Almost surely, 2^61017840 is an apocalyptic number.

61017840 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 61017840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118117440).

61017840 is an abundant number, since it is smaller than the sum of its proper divisors (175217040).

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

61017840 is a wasteful number, since it uses less digits than its factorization.

61017840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 61017840 is about 7811.3916813843. The cubic root of 61017840 is about 393.6880900395.

Adding to 61017840 its reverse (4871016), we get a palindrome (65888856).

The spelling of 61017840 in words is "sixty-one million, seventeen thousand, eight hundred forty".