623399261 has 2 divisors, whose sum is σ = 623399262. Its totient is φ = 623399260.

The previous prime is 623399239. The next prime is 623399267. The reversal of 623399261 is 162993326.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 491287225 + 132112036 = 22165^2 + 11494^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-623399261 is a prime.

It is a super-2 number, since 2×623399261² = 777253277230692242, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (623399267) 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, 311699630 + 311699631.

It is an arithmetic number, because the mean of its divisors is an integer number (311699631).

Almost surely, 2^623399261 is an apocalyptic number.

It is an amenable number.

623399261 is a deficient number, since it is larger than the sum of its proper divisors (1).

623399261 is an equidigital number, since it uses as much as digits as its factorization.

623399261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 104976, while the sum is 41.

The square root of 623399261 is about 24967.9646947844. The cubic root of 623399261 is about 854.2574225752.

The spelling of 623399261 in words is "six hundred twenty-three million, three hundred ninety-nine thousand, two hundred sixty-one".