210172138 has 16 divisors (see below), whose sum is σ = 344727936. Its totient is φ = 95307840.

The previous prime is 210172133. The next prime is 210172147. The reversal of 210172138 is 831271012.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (210172133) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1506 + ... + 20557.

It is an arithmetic number, because the mean of its divisors is an integer number (21545496).

Almost surely, 2^210172138 is an apocalyptic number.

210172138 is a deficient number, since it is larger than the sum of its proper divisors (134555798).

210172138 is a wasteful number, since it uses less digits than its factorization.

210172138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22509.

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 210172138 is about 14497.3148548274. The cubic root of 210172138 is about 594.5545596251.

The spelling of 210172138 in words is "two hundred ten million, one hundred seventy-two thousand, one hundred thirty-eight".