81745432 has 64 divisors (see below), whose sum is σ = 166212000. Its totient is φ = 37610496.

The previous prime is 81745393. The next prime is 81745439. The reversal of 81745432 is 23454718.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81745439) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 763923 + ... + 764029.

Almost surely, 2^81745432 is an apocalyptic number.

It is an amenable number.

81745432 is an abundant number, since it is smaller than the sum of its proper divisors (84466568).

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

81745432 is a wasteful number, since it uses less digits than its factorization.

81745432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268 (or 264 counting only the distinct ones).

The product of its digits is 26880, while the sum is 34.

The square root of 81745432 is about 9041.3180455064. The cubic root of 81745432 is about 433.9981028749.

The spelling of 81745432 in words is "eighty-one million, seven hundred forty-five thousand, four hundred thirty-two".