718621669 has 2 divisors, whose sum is σ = 718621670. Its totient is φ = 718621668.

The previous prime is 718621649. The next prime is 718621679. The reversal of 718621669 is 966126817.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 648313444 + 70308225 = 25462^2 + 8385^2 .

It is an emirp because it is prime and its reverse (966126817) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 718621669 - 2⁹ = 718621157 is a prime.

It is a super-2 number, since 2×718621669² = 1032834206312691122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (718621619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 359310834 + 359310835.

It is an arithmetic number, because the mean of its divisors is an integer number (359310835).

Almost surely, 2^718621669 is an apocalyptic number.

It is an amenable number.

718621669 is a deficient number, since it is larger than the sum of its proper divisors (1).

718621669 is an equidigital number, since it uses as much as digits as its factorization.

718621669 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 46.

The square root of 718621669 is about 26807.1197445753. The cubic root of 718621669 is about 895.7086525673.

The spelling of 718621669 in words is "seven hundred eighteen million, six hundred twenty-one thousand, six hundred sixty-nine".