28007656 has 8 divisors (see below), whose sum is σ = 52514370. Its totient is φ = 14003824.

The previous prime is 28007647. The next prime is 28007671. The reversal of 28007656 is 65670082.

It can be written as a sum of positive squares in only one way, i.e., 16892100 + 11115556 = 4110^2 + 3334^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×28007656² = 1568857589228672, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1750471 + ... + 1750486.

Almost surely, 2^28007656 is an apocalyptic number.

It is an amenable number.

28007656 is a deficient number, since it is larger than the sum of its proper divisors (24506714).

28007656 is a wasteful number, since it uses less digits than its factorization.

28007656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3500963 (or 3500959 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 34.

The square root of 28007656 is about 5292.2259966861. The cubic root of 28007656 is about 303.6865710049.

The spelling of 28007656 in words is "twenty-eight million, seven thousand, six hundred fifty-six".