81333632 has 32 divisors (see below), whose sum is σ = 167626800. Its totient is φ = 39262720.

The previous prime is 81333611. The next prime is 81333643. The reversal of 81333632 is 23633318.

It is a tau number, because it is divible by the number of its divisors (32).

It is a super-2 number, since 2×81333632² = 13230319388622848, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a junction number, because it is equal to n+sod(n) for n = 81333595 and 81333604.

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, 7244 + ... + 14667.

Almost surely, 2^81333632 is an apocalyptic number.

It is an amenable number.

81333632 is an abundant number, since it is smaller than the sum of its proper divisors (86293168).

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

81333632 is a wasteful number, since it uses less digits than its factorization.

81333632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21954 (or 21942 counting only the distinct ones).

The product of its digits is 7776, while the sum is 29.

The square root of 81333632 is about 9018.5160641871. The cubic root of 81333632 is about 433.2681074739.

The spelling of 81333632 in words is "eighty-one million, three hundred thirty-three thousand, six hundred thirty-two".