172320019 has 2 divisors, whose sum is σ = 172320020. Its totient is φ = 172320018.

The previous prime is 172320017. The next prime is 172320073. The reversal of 172320019 is 910023271.

It is a weak prime.

It is an emirp because it is prime and its reverse (910023271) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 172320019 - 2¹ = 172320017 is a prime.

It is a super-2 number, since 2×172320019² = 59388377896320722, which contains 22 as substring.

Together with 172320017, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 172319975 and 172320002.

It is not a weakly prime, because it can be changed into another prime (172320011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86160009 + 86160010.

It is an arithmetic number, because the mean of its divisors is an integer number (86160010).

Almost surely, 2^172320019 is an apocalyptic number.

172320019 is a deficient number, since it is larger than the sum of its proper divisors (1).

172320019 is an equidigital number, since it uses as much as digits as its factorization.

172320019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 172320019 is about 13127.0719888328. The cubic root of 172320019 is about 556.4744701252.

The spelling of 172320019 in words is "one hundred seventy-two million, three hundred twenty thousand, nineteen".