172978379 has 24 divisors (see below), whose sum is σ = 209919600. Its totient is φ = 141994944.

The previous prime is 172978343. The next prime is 172978381. The reversal of 172978379 is 973879271.

It is not a de Polignac number, because 172978379 - 2¹⁶ = 172912843 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 172978379.

It is not an unprimeable number, because it can be changed into a prime (172978319) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 110897 + ... + 112445.

It is an arithmetic number, because the mean of its divisors is an integer number (8746650).

Almost surely, 2^172978379 is an apocalyptic number.

172978379 is a deficient number, since it is larger than the sum of its proper divisors (36941221).

172978379 is a wasteful number, since it uses less digits than its factorization.

172978379 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1659 (or 1652 counting only the distinct ones).

The product of its digits is 1333584, while the sum is 53.

The square root of 172978379 is about 13152.1245051893. The cubic root of 172978379 is about 557.1822519872.

It can be divided in two parts, 1729 and 78379, that added together give a palindrome (80108).

The spelling of 172978379 in words is "one hundred seventy-two million, nine hundred seventy-eight thousand, three hundred seventy-nine".