28172490 has 32 divisors (see below), whose sum is σ = 69797376. Its totient is φ = 7270080.

The previous prime is 28172479. The next prime is 28172513. The reversal of 28172490 is 9427182.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14217 + ... + 16076.

It is an arithmetic number, because the mean of its divisors is an integer number (2181168).

Almost surely, 2^28172490 is an apocalyptic number.

28172490 is an abundant number, since it is smaller than the sum of its proper divisors (41624886).

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

28172490 is a wasteful number, since it uses less digits than its factorization.

28172490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30334.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 28172490 is about 5307.7763705718. The cubic root of 28172490 is about 304.2811702089.

It can be divided in two parts, 281 and 72490, that added together give a triangular number (72771 = T₃₈₁).

The spelling of 28172490 in words is "twenty-eight million, one hundred seventy-two thousand, four hundred ninety".