81658232 has 16 divisors (see below), whose sum is σ = 153206640. Its totient is φ = 40803136.

The previous prime is 81658217. The next prime is 81658237. The reversal of 81658232 is 23285618.

It is a junction number, because it is equal to n+sod(n) for n = 81658192 and 81658201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81658237) 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, 19388 + ... + 23220.

It is an arithmetic number, because the mean of its divisors is an integer number (9575415).

Almost surely, 2^81658232 is an apocalyptic number.

It is an amenable number.

81658232 is a deficient number, since it is larger than the sum of its proper divisors (71548408).

81658232 is a wasteful number, since it uses less digits than its factorization.

81658232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6502 (or 6498 counting only the distinct ones).

The product of its digits is 23040, while the sum is 35.

The square root of 81658232 is about 9036.4944530498. The cubic root of 81658232 is about 433.8437289107.

The spelling of 81658232 in words is "eighty-one million, six hundred fifty-eight thousand, two hundred thirty-two".