81250090 has 8 divisors (see below), whose sum is σ = 146250180. Its totient is φ = 32500032.

The previous prime is 81250073. The next prime is 81250133. The reversal of 81250090 is 9005218.

It can be written as a sum of positive squares in 2 ways, for example, as 75359761 + 5890329 = 8681^2 + 2427^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4062495 + ... + 4062514.

Almost surely, 2^81250090 is an apocalyptic number.

81250090 is a deficient number, since it is larger than the sum of its proper divisors (65000090).

81250090 is a wasteful number, since it uses less digits than its factorization.

81250090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8125016.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 81250090 is about 9013.8831809604. The cubic root of 81250090 is about 433.1197125915.

The spelling of 81250090 in words is "eighty-one million, two hundred fifty thousand, ninety".