81740790 has 48 divisors (see below), whose sum is σ = 212986800. Its totient is φ = 21750336.

The previous prime is 81740779. The next prime is 81740803. The reversal of 81740790 is 9704718.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 65896 + ... + 67124.

It is an arithmetic number, because the mean of its divisors is an integer number (4437225).

Almost surely, 2^81740790 is an apocalyptic number.

81740790 is an abundant number, since it is smaller than the sum of its proper divisors (131246010).

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

81740790 is a wasteful number, since it uses less digits than its factorization.

81740790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1981 (or 1978 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 81740790 is about 9041.0613315031. The cubic root of 81740790 is about 433.9898877071.

The spelling of 81740790 in words is "eighty-one million, seven hundred forty thousand, seven hundred ninety".