81606292 has 24 divisors (see below), whose sum is σ = 150634400. Its totient is φ = 38576736.

The previous prime is 81606269. The next prime is 81606293. The reversal of 81606292 is 29260618.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81606293) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55438 + ... + 56890.

Almost surely, 2^81606292 is an apocalyptic number.

It is an amenable number.

81606292 is a deficient number, since it is larger than the sum of its proper divisors (69028108).

81606292 is a wasteful number, since it uses less digits than its factorization.

81606292 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2215 (or 2213 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 81606292 is about 9033.6200938494. The cubic root of 81606292 is about 433.7517250303.

The spelling of 81606292 in words is "eighty-one million, six hundred six thousand, two hundred ninety-two".