61831620 has 96 divisors (see below), whose sum is σ = 195350400. Its totient is φ = 16232832.

The previous prime is 61831579. The next prime is 61831633. The reversal of 61831620 is 2613816.

61831620 is a `hidden beast` number, since 6 + 1 + 8 + 31 + 620 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 35326 + ... + 37034.

It is an arithmetic number, because the mean of its divisors is an integer number (2034900).

Almost surely, 2^61831620 is an apocalyptic number.

61831620 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 61831620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97675200).

61831620 is an abundant number, since it is smaller than the sum of its proper divisors (133518780).

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

61831620 is a wasteful number, since it uses less digits than its factorization.

61831620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1794 (or 1786 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 61831620 is about 7863.3084639991. The cubic root of 61831620 is about 395.4305405383.

The spelling of 61831620 in words is "sixty-one million, eight hundred thirty-one thousand, six hundred twenty".