172216379 has 2 divisors, whose sum is σ = 172216380. Its totient is φ = 172216378.

The previous prime is 172216367. The next prime is 172216381. The reversal of 172216379 is 973612271.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172216379 is a prime.

Together with 172216381, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (172216679) 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, 86108189 + 86108190.

It is an arithmetic number, because the mean of its divisors is an integer number (86108190).

Almost surely, 2^172216379 is an apocalyptic number.

172216379 is a deficient number, since it is larger than the sum of its proper divisors (1).

172216379 is an equidigital number, since it uses as much as digits as its factorization.

172216379 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31752, while the sum is 38.

The square root of 172216379 is about 13123.1238278087. The cubic root of 172216379 is about 556.3628859139.

The spelling of 172216379 in words is "one hundred seventy-two million, two hundred sixteen thousand, three hundred seventy-nine".