81642966 has 32 divisors (see below), whose sum is σ = 165580800. Its totient is φ = 26834976.

The previous prime is 81642937. The next prime is 81642973. The reversal of 81642966 is 66924618.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 233760 + ... + 234108.

It is an arithmetic number, because the mean of its divisors is an integer number (5174400).

Almost surely, 2^81642966 is an apocalyptic number.

81642966 is an abundant number, since it is smaller than the sum of its proper divisors (83937834).

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

81642966 is a wasteful number, since it uses less digits than its factorization.

81642966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 788.

The product of its digits is 124416, while the sum is 42.

The square root of 81642966 is about 9035.6497276068. The cubic root of 81642966 is about 433.8166915422.

The spelling of 81642966 in words is "eighty-one million, six hundred forty-two thousand, nine hundred sixty-six".