81588942 has 24 divisors (see below), whose sum is σ = 180113544. Its totient is φ = 26682864.

The previous prime is 81588887. The next prime is 81588943. The reversal of 81588942 is 24988518.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81588943) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 41808 + ... + 43715.

It is an arithmetic number, because the mean of its divisors is an integer number (7504731).

Almost surely, 2^81588942 is an apocalyptic number.

81588942 is an abundant number, since it is smaller than the sum of its proper divisors (98524602).

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

81588942 is a wasteful number, since it uses less digits than its factorization.

81588942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85584 (or 85581 counting only the distinct ones).

The product of its digits is 184320, while the sum is 45.

The square root of 81588942 is about 9032.6597411837. The cubic root of 81588942 is about 433.7209834227.

The spelling of 81588942 in words is "eighty-one million, five hundred eighty-eight thousand, nine hundred forty-two".