81961032 has 32 divisors (see below), whose sum is σ = 205152480. Its totient is φ = 27287040.

The previous prime is 81961027. The next prime is 81961043. The reversal of 81961032 is 23016918.

It is a super-2 number, since 2×81961032² = 13435221533010048, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25432 + ... + 28472.

It is an arithmetic number, because the mean of its divisors is an integer number (6411015).

Almost surely, 2^81961032 is an apocalyptic number.

It is an amenable number.

81961032 is an abundant number, since it is smaller than the sum of its proper divisors (123191448).

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

81961032 is a wasteful number, since it uses less digits than its factorization.

81961032 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4173 (or 4169 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 81961032 is about 9053.2332345964. The cubic root of 81961032 is about 434.3793182601.

The spelling of 81961032 in words is "eighty-one million, nine hundred sixty-one thousand, thirty-two".