81526290 has 32 divisors (see below), whose sum is σ = 196534080. Its totient is φ = 21643584.

The previous prime is 81526261. The next prime is 81526297. The reversal of 81526290 is 9262518.

It is a super-2 number, since 2×81526290² = 13293071922328200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81526297) 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, 937 + ... + 12803.

It is an arithmetic number, because the mean of its divisors is an integer number (6141690).

Almost surely, 2^81526290 is an apocalyptic number.

81526290 is an abundant number, since it is smaller than the sum of its proper divisors (115007790).

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

81526290 is a wasteful number, since it uses less digits than its factorization.

81526290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12106.

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 81526290 is about 9029.1909936605. The cubic root of 81526290 is about 433.6099371426.

The spelling of 81526290 in words is "eighty-one million, five hundred twenty-six thousand, two hundred ninety".