28164720 has 40 divisors (see below), whose sum is σ = 87311376. Its totient is φ = 7510528.

The previous prime is 28164691. The next prime is 28164749. The reversal of 28164720 is 2746182.

It is an interprime number because it is at equal distance from previous prime (28164691) and next prime (28164749).

It is a tau number, because it is divible by the number of its divisors (40).

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58437 + ... + 58916.

Almost surely, 2^28164720 is an apocalyptic number.

28164720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28164720 is an abundant number, since it is smaller than the sum of its proper divisors (59146656).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28164720 is a wasteful number, since it uses less digits than its factorization.

28164720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117369 (or 117363 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 28164720 is about 5307.0443751678. The cubic root of 28164720 is about 304.2531939564.

The spelling of 28164720 in words is "twenty-eight million, one hundred sixty-four thousand, seven hundred twenty".