172157002066021 has 12 divisors (see below), whose sum is σ = 200267322074688. Its totient is φ = 147560894043192.

The previous prime is 172157002066003. The next prime is 172157002066097. The reversal of 172157002066021 is 120660200751271.

It is not a de Polignac number, because 172157002066021 - 2¹³ = 172157002057829 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172157002046021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23543151 + ... + 29976556.

It is an arithmetic number, because the mean of its divisors is an integer number (16688943506224).

Almost surely, 2^{172157002066021} is an apocalyptic number.

It is an amenable number.

172157002066021 is a deficient number, since it is larger than the sum of its proper divisors (28110320008667).

172157002066021 is an equidigital number, since it uses as much as digits as its factorization.

172157002066021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53585368 (or 53585361 counting only the distinct ones).

The product of its (nonzero) digits is 70560, while the sum is 40.

The spelling of 172157002066021 in words is "one hundred seventy-two trillion, one hundred fifty-seven billion, two million, sixty-six thousand, twenty-one".