172961729 has 2 divisors, whose sum is σ = 172961730. Its totient is φ = 172961728.

The previous prime is 172961707. The next prime is 172961743. The reversal of 172961729 is 927169271.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 126517504 + 46444225 = 11248^2 + 6815^2 .

It is a cyclic number.

It is not a de Polignac number, because 172961729 - 2⁸ = 172961473 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 172961729.

It is not a weakly prime, because it can be changed into another prime (172961029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86480864 + 86480865.

It is an arithmetic number, because the mean of its divisors is an integer number (86480865).

Almost surely, 2^172961729 is an apocalyptic number.

It is an amenable number.

172961729 is a deficient number, since it is larger than the sum of its proper divisors (1).

172961729 is an equidigital number, since it uses as much as digits as its factorization.

172961729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 95256, while the sum is 44.

The square root of 172961729 is about 13151.4915123723. The cubic root of 172961729 is about 557.1643742574.

The spelling of 172961729 in words is "one hundred seventy-two million, nine hundred sixty-one thousand, seven hundred twenty-nine".