641319021 has 24 divisors (see below), whose sum is σ = 1095194880. Its totient is φ = 353830176.

The previous prime is 641319017. The next prime is 641319023. The reversal of 641319021 is 120913146.

641319021 is a `hidden beast` number, since 641 + 3 + 19 + 0 + 2 + 1 = 666.

It is not a de Polignac number, because 641319021 - 2² = 641319017 is a prime.

It is a super-2 number, since 2×641319021² = 822580173392796882, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641319023) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 173685 + ... + 177338.

It is an arithmetic number, because the mean of its divisors is an integer number (45633120).

Almost surely, 2^641319021 is an apocalyptic number.

It is an amenable number.

641319021 is a deficient number, since it is larger than the sum of its proper divisors (453875859).

641319021 is a wasteful number, since it uses less digits than its factorization.

641319021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351065 (or 351062 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 641319021 is about 25324.2773045945. The cubic root of 641319021 is about 862.3654998838.

The spelling of 641319021 in words is "six hundred forty-one million, three hundred nineteen thousand, twenty-one".