81542492 has 12 divisors (see below), whose sum is σ = 142855776. Its totient is φ = 40726560.

The previous prime is 81542479. The next prime is 81542497. The reversal of 81542492 is 29424518.

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81542497) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6884 + ... + 14507.

It is an arithmetic number, because the mean of its divisors is an integer number (11904648).

Almost surely, 2^81542492 is an apocalyptic number.

It is an amenable number.

81542492 is a deficient number, since it is larger than the sum of its proper divisors (61313284).

81542492 is a wasteful number, since it uses less digits than its factorization.

81542492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22348 (or 22346 counting only the distinct ones).

The product of its digits is 23040, while the sum is 35.

The square root of 81542492 is about 9030.0881501788. The cubic root of 81542492 is about 433.6386595047.

The spelling of 81542492 in words is "eighty-one million, five hundred forty-two thousand, four hundred ninety-two".