172109156 has 12 divisors (see below), whose sum is σ = 318908268. Its totient is φ = 80992512.

The previous prime is 172109153. The next prime is 172109167. The reversal of 172109156 is 651901271.

It can be written as a sum of positive squares in 2 ways, for example, as 81288256 + 90820900 = 9016^2 + 9530^2 .

It is not an unprimeable number, because it can be changed into a prime (172109153) 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 in 3 ways as a sum of consecutive naturals, for example, 1265441 + ... + 1265576.

It is an arithmetic number, because the mean of its divisors is an integer number (26575689).

Almost surely, 2^172109156 is an apocalyptic number.

It is an amenable number.

172109156 is a deficient number, since it is larger than the sum of its proper divisors (146799112).

172109156 is a wasteful number, since it uses less digits than its factorization.

172109156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2531038 (or 2531036 counting only the distinct ones).

The product of its (nonzero) digits is 3780, while the sum is 32.

The square root of 172109156 is about 13119.0379220429. The cubic root of 172109156 is about 556.2473969326.

The spelling of 172109156 in words is "one hundred seventy-two million, one hundred nine thousand, one hundred fifty-six".