398742623 has 2 divisors, whose sum is σ = 398742624. Its totient is φ = 398742622.

The previous prime is 398742613. The next prime is 398742629. The reversal of 398742623 is 326247893.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 398742623 - 2²⁴ = 381965407 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (398742629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199371311 + 199371312.

It is an arithmetic number, because the mean of its divisors is an integer number (199371312).

Almost surely, 2^398742623 is an apocalyptic number.

398742623 is a deficient number, since it is larger than the sum of its proper divisors (1).

398742623 is an equidigital number, since it uses as much as digits as its factorization.

398742623 is an evil number, because the sum of its binary digits is even.

The product of its digits is 435456, while the sum is 44.

The square root of 398742623 is about 19968.5408330203. The cubic root of 398742623 is about 736.0334532831.

The spelling of 398742623 in words is "three hundred ninety-eight million, seven hundred forty-two thousand, six hundred twenty-three".