172398643 has 2 divisors, whose sum is σ = 172398644. Its totient is φ = 172398642.

The previous prime is 172398631. The next prime is 172398661. The reversal of 172398643 is 346893271.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 172398643 - 2⁹ = 172398131 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 172398643.

It is not a weakly prime, because it can be changed into another prime (172398623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86199321 + 86199322.

It is an arithmetic number, because the mean of its divisors is an integer number (86199322).

Almost surely, 2^172398643 is an apocalyptic number.

172398643 is a deficient number, since it is larger than the sum of its proper divisors (1).

172398643 is an equidigital number, since it uses as much as digits as its factorization.

172398643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 43.

The square root of 172398643 is about 13130.0663745466. The cubic root of 172398643 is about 556.5590909689.

The spelling of 172398643 in words is "one hundred seventy-two million, three hundred ninety-eight thousand, six hundred forty-three".