84172257 has 16 divisors (see below), whose sum is σ = 134292480. Its totient is φ = 51798096.

The previous prime is 84172247. The next prime is 84172259. The reversal of 84172257 is 75227148.

It is not a de Polignac number, because 84172257 - 2⁸ = 84172001 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (84172259) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 119553 + ... + 120254.

It is an arithmetic number, because the mean of its divisors is an integer number (8393280).

Almost surely, 2^84172257 is an apocalyptic number.

It is an amenable number.

84172257 is a deficient number, since it is larger than the sum of its proper divisors (50120223).

84172257 is a wasteful number, since it uses less digits than its factorization.

84172257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239829 (or 239823 counting only the distinct ones).

The product of its digits is 31360, while the sum is 36.

The square root of 84172257 is about 9174.5439668683. The cubic root of 84172257 is about 438.2510757888.

The spelling of 84172257 in words is "eighty-four million, one hundred seventy-two thousand, two hundred fifty-seven".