172942321 has 2 divisors, whose sum is σ = 172942322. Its totient is φ = 172942320.

The previous prime is 172942307. The next prime is 172942333. The reversal of 172942321 is 123249271.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 98724096 + 74218225 = 9936^2 + 8615^2 .

It is a cyclic number.

It is not a de Polignac number, because 172942321 - 2⁷ = 172942193 is a prime.

It is not a weakly prime, because it can be changed into another prime (172940321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86471160 + 86471161.

It is an arithmetic number, because the mean of its divisors is an integer number (86471161).

Almost surely, 2^172942321 is an apocalyptic number.

It is an amenable number.

172942321 is a deficient number, since it is larger than the sum of its proper divisors (1).

172942321 is an equidigital number, since it uses as much as digits as its factorization.

172942321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 31.

The square root of 172942321 is about 13150.7536285948. The cubic root of 172942321 is about 557.1435337113.

The spelling of 172942321 in words is "one hundred seventy-two million, nine hundred forty-two thousand, three hundred twenty-one".