61691256 has 48 divisors (see below), whose sum is σ = 182271960. Its totient is φ = 18694080.

The previous prime is 61691251. The next prime is 61691263. The reversal of 61691256 is 65219616.

It is a super-2 number, since 2×61691256² = 7611622133715072, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 61691256.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61691251) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38155 + ... + 39738.

Almost surely, 2^61691256 is an apocalyptic number.

61691256 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

61691256 is an abundant number, since it is smaller than the sum of its proper divisors (120580704).

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

61691256 is a wasteful number, since it uses less digits than its factorization.

61691256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77916 (or 77909 counting only the distinct ones).

The product of its digits is 19440, while the sum is 36.

The square root of 61691256 is about 7854.3781421574. The cubic root of 61691256 is about 395.1310914566.

The spelling of 61691256 in words is "sixty-one million, six hundred ninety-one thousand, two hundred fifty-six".