172899971 has 2 divisors, whose sum is σ = 172899972. Its totient is φ = 172899970.

The previous prime is 172899949. The next prime is 172899973. The reversal of 172899971 is 179998271.

172899971 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is an emirp because it is prime and its reverse (179998271) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172899971 is a prime.

Together with 172899973, 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 (172899973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86449985 + 86449986.

It is an arithmetic number, because the mean of its divisors is an integer number (86449986).

Almost surely, 2^172899971 is an apocalyptic number.

172899971 is a deficient number, since it is larger than the sum of its proper divisors (1).

172899971 is an equidigital number, since it uses as much as digits as its factorization.

172899971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 571536, while the sum is 53.

The square root of 172899971 is about 13149.1433561278. The cubic root of 172899971 is about 557.0980523532.

The spelling of 172899971 in words is "one hundred seventy-two million, eight hundred ninety-nine thousand, nine hundred seventy-one".