81413658 has 24 divisors (see below), whose sum is σ = 176728500. Its totient is φ = 27086784.

The previous prime is 81413639. The next prime is 81413681. The reversal of 81413658 is 85631418.

It can be written as a sum of positive squares in 2 ways, for example, as 78375609 + 3038049 = 8853^2 + 1743^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6268 + ... + 14216.

Almost surely, 2^81413658 is an apocalyptic number.

81413658 is an abundant number, since it is smaller than the sum of its proper divisors (95314842).

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

81413658 is a wasteful number, since it uses less digits than its factorization.

81413658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8526 (or 8523 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 81413658 is about 9022.9517343273. The cubic root of 81413658 is about 433.4101616573.

The spelling of 81413658 in words is "eighty-one million, four hundred thirteen thousand, six hundred fifty-eight".