81632658 has 32 divisors (see below), whose sum is σ = 172440576. Its totient is φ = 25710608.

The previous prime is 81632653. The next prime is 81632671. The reversal of 81632658 is 85623618.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (81632653) 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, 7891 + ... + 15017.

It is an arithmetic number, because the mean of its divisors is an integer number (5388768).

Almost surely, 2^81632658 is an apocalyptic number.

81632658 is an abundant number, since it is smaller than the sum of its proper divisors (90807918).

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

81632658 is a wasteful number, since it uses less digits than its factorization.

81632658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7238.

The product of its digits is 69120, while the sum is 39.

The square root of 81632658 is about 9035.0793023636. The cubic root of 81632658 is about 433.7984333019.

The spelling of 81632658 in words is "eighty-one million, six hundred thirty-two thousand, six hundred fifty-eight".