81539050 has 12 divisors (see below), whose sum is σ = 151662726. Its totient is φ = 32615600.

The previous prime is 81539047. The next prime is 81539063. The reversal of 81539050 is 5093518.

It can be written as a sum of positive squares in 3 ways, for example, as 43309561 + 38229489 = 6581^2 + 6183^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 815341 + ... + 815440.

Almost surely, 2^81539050 is an apocalyptic number.

81539050 is a deficient number, since it is larger than the sum of its proper divisors (70123676).

81539050 is a wasteful number, since it uses less digits than its factorization.

81539050 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1630793 (or 1630788 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 31.

The square root of 81539050 is about 9029.8975630956. The cubic root of 81539050 is about 433.6325579609.

The spelling of 81539050 in words is "eighty-one million, five hundred thirty-nine thousand, fifty".