28215464 has 8 divisors (see below), whose sum is σ = 52904010. Its totient is φ = 14107728.

The previous prime is 28215431. The next prime is 28215469. The reversal of 28215464 is 46451282.

It can be written as a sum of positive squares in only one way, i.e., 14212900 + 14002564 = 3770^2 + 3742^2 .

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

It is a super-2 number, since 2×28215464² = 1592224817470592, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28215464.

It is not an unprimeable number, because it can be changed into a prime (28215469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1763459 + ... + 1763474.

Almost surely, 2^28215464 is an apocalyptic number.

It is an amenable number.

28215464 is a deficient number, since it is larger than the sum of its proper divisors (24688546).

28215464 is a wasteful number, since it uses less digits than its factorization.

28215464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3526939 (or 3526935 counting only the distinct ones).

The product of its digits is 15360, while the sum is 32.

The square root of 28215464 is about 5311.8230392211. The cubic root of 28215464 is about 304.4358073021.

The spelling of 28215464 in words is "twenty-eight million, two hundred fifteen thousand, four hundred sixty-four".