172632991 has 2 divisors, whose sum is σ = 172632992. Its totient is φ = 172632990.

The previous prime is 172632983. The next prime is 172633007. The reversal of 172632991 is 199236271.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 172632991 - 2³ = 172632983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (172632931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86316495 + 86316496.

It is an arithmetic number, because the mean of its divisors is an integer number (86316496).

Almost surely, 2^172632991 is an apocalyptic number.

172632991 is a deficient number, since it is larger than the sum of its proper divisors (1).

172632991 is an equidigital number, since it uses as much as digits as its factorization.

172632991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 40.

The square root of 172632991 is about 13138.9874419607. The cubic root of 172632991 is about 556.8111607326.

The spelling of 172632991 in words is "one hundred seventy-two million, six hundred thirty-two thousand, nine hundred ninety-one".