81393432 has 16 divisors (see below), whose sum is σ = 203483640. Its totient is φ = 27131136.

The previous prime is 81393427. The next prime is 81393457. The reversal of 81393432 is 23439318.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 81393393 and 81393402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1695673 + ... + 1695720.

Almost surely, 2^81393432 is an apocalyptic number.

It is an amenable number.

81393432 is an abundant number, since it is smaller than the sum of its proper divisors (122090208).

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

81393432 is a wasteful number, since it uses less digits than its factorization.

81393432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3391402 (or 3391398 counting only the distinct ones).

The product of its digits is 15552, while the sum is 33.

The square root of 81393432 is about 9021.8308563174. The cubic root of 81393432 is about 433.3742672705.

The spelling of 81393432 in words is "eighty-one million, three hundred ninety-three thousand, four hundred thirty-two".