172121200117 has 16 divisors (see below), whose sum is σ = 175759653888. Its totient is φ = 168526491840.

The previous prime is 172121200039. The next prime is 172121200169. The reversal of 172121200117 is 711002121271.

It is a cyclic number.

It is not a de Polignac number, because 172121200117 - 2⁷ = 172121199989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 172121200091 and 172121200100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172121203117) 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, 4382188 + ... + 4421290.

It is an arithmetic number, because the mean of its divisors is an integer number (10984978368).

Almost surely, 2^172121200117 is an apocalyptic number.

It is an amenable number.

172121200117 is a deficient number, since it is larger than the sum of its proper divisors (3638453771).

172121200117 is a wasteful number, since it uses less digits than its factorization.

172121200117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39660.

The product of its (nonzero) digits is 392, while the sum is 25.

Adding to 172121200117 its reverse (711002121271), we get a palindrome (883123321388).

The spelling of 172121200117 in words is "one hundred seventy-two billion, one hundred twenty-one million, two hundred thousand, one hundred seventeen".