81155832 has 16 divisors (see below), whose sum is σ = 202889640. Its totient is φ = 27051936.

The previous prime is 81155819. The next prime is 81155839. The reversal of 81155832 is 23855118.

It is a happy number.

It is a super-2 number, since 2×81155832² = 13172538135224448, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81155793 and 81155802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81155839) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1690723 + ... + 1690770.

Almost surely, 2^81155832 is an apocalyptic number.

It is an amenable number.

81155832 is an abundant number, since it is smaller than the sum of its proper divisors (121733808).

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

81155832 is a wasteful number, since it uses less digits than its factorization.

81155832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3381502 (or 3381498 counting only the distinct ones).

The product of its digits is 9600, while the sum is 33.

The square root of 81155832 is about 9008.6531734772. The cubic root of 81155832 is about 432.9521607974.

The spelling of 81155832 in words is "eighty-one million, one hundred fifty-five thousand, eight hundred thirty-two".