28687664 has 10 divisors (see below), whose sum is σ = 55582380. Its totient is φ = 14343824.

The previous prime is 28687661. The next prime is 28687667. The reversal of 28687664 is 46678682.

It is an interprime number because it is at equal distance from previous prime (28687661) and next prime (28687667).

It is not an unprimeable number, because it can be changed into a prime (28687661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 896474 + ... + 896505.

It is an arithmetic number, because the mean of its divisors is an integer number (5558238).

Almost surely, 2^28687664 is an apocalyptic number.

It is an amenable number.

28687664 is a deficient number, since it is larger than the sum of its proper divisors (26894716).

28687664 is a wasteful number, since it uses less digits than its factorization.

28687664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1792987 (or 1792981 counting only the distinct ones).

The product of its digits is 774144, while the sum is 47.

The square root of 28687664 is about 5356.0866311142. The cubic root of 28687664 is about 306.1247159903.

The spelling of 28687664 in words is "twenty-eight million, six hundred eighty-seven thousand, six hundred sixty-four".