81352990 has 64 divisors (see below), whose sum is σ = 164229120. Its totient is φ = 28869120.

The previous prime is 81352981. The next prime is 81353011. The reversal of 81352990 is 9925318.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 226431 + ... + 226789.

It is an arithmetic number, because the mean of its divisors is an integer number (2566080).

Almost surely, 2^81352990 is an apocalyptic number.

81352990 is an abundant number, since it is smaller than the sum of its proper divisors (82876130).

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

81352990 is a wasteful number, since it uses less digits than its factorization.

81352990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 457.

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 81352990 is about 9019.5892367668. The cubic root of 81352990 is about 433.3024784079.

The spelling of 81352990 in words is "eighty-one million, three hundred fifty-two thousand, nine hundred ninety".