172122239561 has 2 divisors, whose sum is σ = 172122239562. Its totient is φ = 172122239560.

The previous prime is 172122239539. The next prime is 172122239567. The reversal of 172122239561 is 165932221271.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 152478535225 + 19643704336 = 390485^2 + 140156^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172122239561 is a prime.

It is not a weakly prime, because it can be changed into another prime (172122239567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86061119780 + 86061119781.

It is an arithmetic number, because the mean of its divisors is an integer number (86061119781).

Almost surely, 2^172122239561 is an apocalyptic number.

It is an amenable number.

172122239561 is a deficient number, since it is larger than the sum of its proper divisors (1).

172122239561 is an equidigital number, since it uses as much as digits as its factorization.

172122239561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 41.

The spelling of 172122239561 in words is "one hundred seventy-two billion, one hundred twenty-two million, two hundred thirty-nine thousand, five hundred sixty-one".