28921886 has 32 divisors (see below), whose sum is σ = 51321600. Its totient is φ = 11966976.

The previous prime is 28921883. The next prime is 28921891. The reversal of 28921886 is 68812982.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28921883) 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, 64190 + ... + 64638.

It is an arithmetic number, because the mean of its divisors is an integer number (1603800).

Almost surely, 2^28921886 is an apocalyptic number.

28921886 is a deficient number, since it is larger than the sum of its proper divisors (22399714).

28921886 is a wasteful number, since it uses less digits than its factorization.

28921886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 608.

The product of its digits is 110592, while the sum is 44.

The square root of 28921886 is about 5377.9072137775. The cubic root of 28921886 is about 306.9555828464.

The spelling of 28921886 in words is "twenty-eight million, nine hundred twenty-one thousand, eight hundred eighty-six".