81662612 has 24 divisors (see below), whose sum is σ = 146627712. Its totient is φ = 39780000.

The previous prime is 81662563. The next prime is 81662653. The reversal of 81662612 is 21626618.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30737 + ... + 33287.

It is an arithmetic number, because the mean of its divisors is an integer number (6109488).

Almost surely, 2^81662612 is an apocalyptic number.

It is an amenable number.

81662612 is a deficient number, since it is larger than the sum of its proper divisors (64965100).

81662612 is a wasteful number, since it uses less digits than its factorization.

81662612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2759 (or 2757 counting only the distinct ones).

The product of its digits is 6912, while the sum is 32.

The square root of 81662612 is about 9036.7368004164. The cubic root of 81662612 is about 433.8514856366.

The spelling of 81662612 in words is "eighty-one million, six hundred sixty-two thousand, six hundred twelve".