28507990 has 16 divisors (see below), whose sum is σ = 58645152. Its totient is φ = 9774144.

The previous prime is 28507987. The next prime is 28508027. The reversal of 28507990 is 9970582.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 203559 + ... + 203698.

It is an arithmetic number, because the mean of its divisors is an integer number (3665322).

Almost surely, 2^28507990 is an apocalyptic number.

28507990 is an abundant number, since it is smaller than the sum of its proper divisors (30137162).

28507990 is a wasteful number, since it uses less digits than its factorization.

28507990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407271.

The product of its (nonzero) digits is 45360, while the sum is 40.

The square root of 28507990 is about 5339.2874056376. The cubic root of 28507990 is about 305.4842794753.

The spelling of 28507990 in words is "twenty-eight million, five hundred seven thousand, nine hundred ninety".