81790554 has 32 divisors (see below), whose sum is σ = 175452480. Its totient is φ = 25339392.

The previous prime is 81790547. The next prime is 81790559. The reversal of 81790554 is 45509718.

It is not an unprimeable number, because it can be changed into a prime (81790559) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 727 + ... + 12810.

It is an arithmetic number, because the mean of its divisors is an integer number (5482890).

Almost surely, 2^81790554 is an apocalyptic number.

81790554 is an abundant number, since it is smaller than the sum of its proper divisors (93661926).

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

81790554 is a wasteful number, since it uses less digits than its factorization.

81790554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13614.

The product of its (nonzero) digits is 50400, while the sum is 39.

The square root of 81790554 is about 9043.8130232773. The cubic root of 81790554 is about 434.0779412214.

The spelling of 81790554 in words is "eighty-one million, seven hundred ninety thousand, five hundred fifty-four".