623839681 has 2 divisors, whose sum is σ = 623839682. Its totient is φ = 623839680.

The previous prime is 623839661. The next prime is 623839693. The reversal of 623839681 is 186938326.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 451180081 + 172659600 = 21241^2 + 13140^2 .

It is a cyclic number.

It is not a de Polignac number, because 623839681 - 2⁷ = 623839553 is a prime.

It is a super-2 number, since 2×623839681² = 778351895180363522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (623839661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 311919840 + 311919841.

It is an arithmetic number, because the mean of its divisors is an integer number (311919841).

Almost surely, 2^623839681 is an apocalyptic number.

It is an amenable number.

623839681 is a deficient number, since it is larger than the sum of its proper divisors (1).

623839681 is an equidigital number, since it uses as much as digits as its factorization.

623839681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 373248, while the sum is 46.

The square root of 623839681 is about 24976.7828392690. The cubic root of 623839681 is about 854.4585475534.

The spelling of 623839681 in words is "six hundred twenty-three million, eight hundred thirty-nine thousand, six hundred eighty-one".