81632628 has 144 divisors (see below), whose sum is σ = 262953600. Its totient is φ = 21168000.

The previous prime is 81632627. The next prime is 81632633. The reversal of 81632628 is 82623618.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 81632592 and 81632601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81632627) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 135528 + ... + 136128.

Almost surely, 2^81632628 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81632628, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131476800).

81632628 is an abundant number, since it is smaller than the sum of its proper divisors (181320972).

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

81632628 is a wasteful number, since it uses less digits than its factorization.

81632628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 643 (or 624 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 81632628 is about 9035.0776421678. The cubic root of 81632628 is about 433.7983801616.

The spelling of 81632628 in words is "eighty-one million, six hundred thirty-two thousand, six hundred twenty-eight".