81707532 has 24 divisors (see below), whose sum is σ = 190957872. Its totient is φ = 27192000.

The previous prime is 81707519. The next prime is 81707539. The reversal of 81707532 is 23570718.

It is a super-2 number, since 2×81707532² = 13352241571062048, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81707493 and 81707502.

It is not an unprimeable number, because it can be changed into a prime (81707539) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2782 + ... + 13082.

It is an arithmetic number, because the mean of its divisors is an integer number (7956578).

Almost surely, 2^81707532 is an apocalyptic number.

It is an amenable number.

81707532 is an abundant number, since it is smaller than the sum of its proper divisors (109250340).

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

81707532 is a wasteful number, since it uses less digits than its factorization.

81707532 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10969 (or 10967 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 33.

The square root of 81707532 is about 9039.2218691655. The cubic root of 81707532 is about 433.9310203465.

The spelling of 81707532 in words is "eighty-one million, seven hundred seven thousand, five hundred thirty-two".