641571899 has 2 divisors, whose sum is σ = 641571900. Its totient is φ = 641571898.

The previous prime is 641571863. The next prime is 641571907. The reversal of 641571899 is 998175146.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-641571899 is a prime.

It is a super-2 number, since 2×641571899² = 823229003172932402, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (641571809) 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, 320785949 + 320785950.

It is an arithmetic number, because the mean of its divisors is an integer number (320785950).

Almost surely, 2^641571899 is an apocalyptic number.

641571899 is a deficient number, since it is larger than the sum of its proper divisors (1).

641571899 is an equidigital number, since it uses as much as digits as its factorization.

641571899 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 50.

The square root of 641571899 is about 25329.2696104724. The cubic root of 641571899 is about 862.4788312105.

The spelling of 641571899 in words is "six hundred forty-one million, five hundred seventy-one thousand, eight hundred ninety-nine".