28921490 has 32 divisors (see below), whose sum is σ = 56306880. Its totient is φ = 10632384.

The previous prime is 28921489. The next prime is 28921507. The reversal of 28921490 is 9412982.

It is a self number, because there is not a number n which added to its sum of digits gives 28921490.

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, 48977 + ... + 49563.

It is an arithmetic number, because the mean of its divisors is an integer number (1759590).

Almost surely, 2^28921490 is an apocalyptic number.

28921490 is a deficient number, since it is larger than the sum of its proper divisors (27385390).

28921490 is a wasteful number, since it uses less digits than its factorization.

28921490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 986.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 28921490 is about 5377.8703963558. The cubic root of 28921490 is about 306.9541818893.

The spelling of 28921490 in words is "twenty-eight million, nine hundred twenty-one thousand, four hundred ninety".