81767290 has 16 divisors (see below), whose sum is σ = 160561440. Its totient is φ = 29733520.

The previous prime is 81767251. The next prime is 81767419. The reversal of 81767290 is 9276718.

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, 371560 + ... + 371779.

It is an arithmetic number, because the mean of its divisors is an integer number (10035090).

Almost surely, 2^81767290 is an apocalyptic number.

81767290 is a deficient number, since it is larger than the sum of its proper divisors (78794150).

81767290 is a wasteful number, since it uses less digits than its factorization.

81767290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 743357.

The product of its (nonzero) digits is 42336, while the sum is 40.

The square root of 81767290 is about 9042.5267486472. The cubic root of 81767290 is about 434.0367818359.

The spelling of 81767290 in words is "eighty-one million, seven hundred sixty-seven thousand, two hundred ninety".