172120051 has 4 divisors (see below), whose sum is σ = 175037400. Its totient is φ = 169202704.

The previous prime is 172120049. The next prime is 172120103. The reversal of 172120051 is 150021271.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 172120051 - 2¹ = 172120049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172120951) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1458586 + ... + 1458703.

It is an arithmetic number, because the mean of its divisors is an integer number (43759350).

Almost surely, 2^172120051 is an apocalyptic number.

172120051 is a deficient number, since it is larger than the sum of its proper divisors (2917349).

172120051 is an equidigital number, since it uses as much as digits as its factorization.

172120051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2917348.

The product of its (nonzero) digits is 140, while the sum is 19.

The square root of 172120051 is about 13119.4531517133. The cubic root of 172120051 is about 556.2591340334.

The spelling of 172120051 in words is "one hundred seventy-two million, one hundred twenty thousand, fifty-one".