641399999 has 2 divisors, whose sum is σ = 641400000. Its totient is φ = 641399998.

The previous prime is 641399981. The next prime is 641400017. The reversal of 641399999 is 999993146.

It is a balanced prime because it is at equal distance from previous prime (641399981) and next prime (641400017).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-641399999 is a prime.

It is a super-2 number, since 2×641399999² = 822787917434400002, which contains 22 as substring.

641399999 is a modest number, since divided by 99999 gives 6413 as remainder.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641399939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320699999 + 320700000.

It is an arithmetic number, because the mean of its divisors is an integer number (320700000).

Almost surely, 2^641399999 is an apocalyptic number.

641399999 is a deficient number, since it is larger than the sum of its proper divisors (1).

641399999 is an equidigital number, since it uses as much as digits as its factorization.

641399999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4251528, while the sum is 59.

The square root of 641399999 is about 25325.8760756662. The cubic root of 641399999 is about 862.4017947138.

The spelling of 641399999 in words is "six hundred forty-one million, three hundred ninety-nine thousand, nine hundred ninety-nine".