81935670 has 16 divisors (see below), whose sum is σ = 196645680. Its totient is φ = 21849504.

The previous prime is 81935669. The next prime is 81935743. The reversal of 81935670 is 7653918.

It is a congruent number.

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, 1365565 + ... + 1365624.

It is an arithmetic number, because the mean of its divisors is an integer number (12290355).

Almost surely, 2^81935670 is an apocalyptic number.

81935670 is an abundant number, since it is smaller than the sum of its proper divisors (114710010).

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

81935670 is a wasteful number, since it uses less digits than its factorization.

81935670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2731199.

The product of its (nonzero) digits is 45360, while the sum is 39.

The square root of 81935670 is about 9051.8324111751. The cubic root of 81935670 is about 434.3345088975.

The spelling of 81935670 in words is "eighty-one million, nine hundred thirty-five thousand, six hundred seventy".