28172079 has 72 divisors (see below), whose sum is σ = 49926240. Its totient is φ = 15168384.

The previous prime is 28172069. The next prime is 28172147. The reversal of 28172079 is 97027182.

It is not a de Polignac number, because 28172079 - 2⁴ = 28172063 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28172069) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 971437 + ... + 971465.

It is an arithmetic number, because the mean of its divisors is an integer number (693420).

Almost surely, 2^28172079 is an apocalyptic number.

28172079 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

28172079 is a deficient number, since it is larger than the sum of its proper divisors (21754161).

28172079 is a wasteful number, since it uses less digits than its factorization.

28172079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109 (or 87 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 28172079 is about 5307.7376536524. The cubic root of 28172079 is about 304.2796905128.

The spelling of 28172079 in words is "twenty-eight million, one hundred seventy-two thousand, seventy-nine".