634923389 has 2 divisors, whose sum is σ = 634923390. Its totient is φ = 634923388.

The previous prime is 634923379. The next prime is 634923391. The reversal of 634923389 is 983329436.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 437520889 + 197402500 = 20917^2 + 14050^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-634923389 is a prime.

Together with 634923391, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (634923379) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 317461694 + 317461695.

It is an arithmetic number, because the mean of its divisors is an integer number (317461695).

Almost surely, 2^634923389 is an apocalyptic number.

It is an amenable number.

634923389 is a deficient number, since it is larger than the sum of its proper divisors (1).

634923389 is an equidigital number, since it uses as much as digits as its factorization.

634923389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 839808, while the sum is 47.

The square root of 634923389 is about 25197.6861834574. The cubic root of 634923389 is about 859.4892356509.

It can be divided in two parts, 6349 and 23389, that multiplied together give a triangular number (148496761 = T₁₇₂₃₃).

The spelling of 634923389 in words is "six hundred thirty-four million, nine hundred twenty-three thousand, three hundred eighty-nine".