81250028 has 48 divisors (see below), whose sum is σ = 151732224. Its totient is φ = 38021760.

The previous prime is 81250027. The next prime is 81250033. The reversal of 81250028 is 82005218.

It is a junction number, because it is equal to n+sod(n) for n = 81249979 and 81250006.

It is not an unprimeable number, because it can be changed into a prime (81250027) 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, 639701 + ... + 639827.

It is an arithmetic number, because the mean of its divisors is an integer number (3161088).

Almost surely, 2^81250028 is an apocalyptic number.

It is an amenable number.

81250028 is a deficient number, since it is larger than the sum of its proper divisors (70482196).

81250028 is a wasteful number, since it uses less digits than its factorization.

81250028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302 (or 300 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 26.

The square root of 81250028 is about 9013.8797418204. The cubic root of 81250028 is about 433.1196024237.

The spelling of 81250028 in words is "eighty-one million, two hundred fifty thousand, twenty-eight".