172667491 has 2 divisors, whose sum is σ = 172667492. Its totient is φ = 172667490.

The previous prime is 172667477. The next prime is 172667513. The reversal of 172667491 is 194766271.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 172667491 - 2⁹ = 172666979 is a prime.

It is not a weakly prime, because it can be changed into another prime (172667431) 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 as a sum of consecutive naturals, namely, 86333745 + 86333746.

It is an arithmetic number, because the mean of its divisors is an integer number (86333746).

Almost surely, 2^172667491 is an apocalyptic number.

172667491 is a deficient number, since it is larger than the sum of its proper divisors (1).

172667491 is an equidigital number, since it uses as much as digits as its factorization.

172667491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 127008, while the sum is 43.

The square root of 172667491 is about 13140.3002629316. The cubic root of 172667491 is about 556.8482504094.

The spelling of 172667491 in words is "one hundred seventy-two million, six hundred sixty-seven thousand, four hundred ninety-one".