81542522 has 16 divisors (see below), whose sum is σ = 126270144. Its totient is φ = 39468000.

The previous prime is 81542507. The next prime is 81542581. The reversal of 81542522 is 22524518.

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, 6947 + ... + 14537.

It is an arithmetic number, because the mean of its divisors is an integer number (7891884).

Almost surely, 2^81542522 is an apocalyptic number.

81542522 is a gapful number since it is divisible by the number (82) formed by its first and last digit.

81542522 is a deficient number, since it is larger than the sum of its proper divisors (44727622).

81542522 is a wasteful number, since it uses less digits than its factorization.

81542522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7765.

The product of its digits is 6400, while the sum is 29.

The square root of 81542522 is about 9030.0898112920. The cubic root of 81542522 is about 433.6387126842.

The spelling of 81542522 in words is "eighty-one million, five hundred forty-two thousand, five hundred twenty-two".