172121753 has 6 divisors (see below), whose sum is σ = 182842446. Its totient is φ = 161996672.

The previous prime is 172121749. The next prime is 172121767. The reversal of 172121753 is 357121271.

It can be written as a sum of positive squares in 3 ways, for example, as 112105744 + 60016009 = 10588^2 + 7747^2 .

It is not a de Polignac number, because 172121753 - 2² = 172121749 is a prime.

It is not an unprimeable number, because it can be changed into a prime (172121783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 297500 + ... + 298077.

It is an arithmetic number, because the mean of its divisors is an integer number (30473741).

Almost surely, 2^172121753 is an apocalyptic number.

It is an amenable number.

172121753 is a deficient number, since it is larger than the sum of its proper divisors (10720693).

172121753 is an equidigital number, since it uses as much as digits as its factorization.

172121753 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 595611 (or 595594 counting only the distinct ones).

The product of its digits is 2940, while the sum is 29.

The square root of 172121753 is about 13119.5180170614. The cubic root of 172121753 is about 556.2609675403.

The spelling of 172121753 in words is "one hundred seventy-two million, one hundred twenty-one thousand, seven hundred fifty-three".