81307935 has 32 divisors (see below), whose sum is σ = 152160000. Its totient is φ = 41080608.

The previous prime is 81307927. The next prime is 81307939. The reversal of 81307935 is 53970318.

It is not a de Polignac number, because 81307935 - 2³ = 81307927 is a prime.

It is a super-2 number, since 2×81307935² = 13221960587928450, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81307935.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81307939) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13285 + ... + 18414.

It is an arithmetic number, because the mean of its divisors is an integer number (4755000).

Almost surely, 2^81307935 is an apocalyptic number.

81307935 is a deficient number, since it is larger than the sum of its proper divisors (70852065).

81307935 is a wasteful number, since it uses less digits than its factorization.

81307935 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31732 (or 31726 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 36.

The square root of 81307935 is about 9017.0912715798. The cubic root of 81307935 is about 433.2224729558. Note that the first 3 decimals are identical.

The spelling of 81307935 in words is "eighty-one million, three hundred seven thousand, nine hundred thirty-five".