641147921 has 16 divisors (see below), whose sum is σ = 686400000. Its totient is φ = 597542400.

The previous prime is 641147917. The next prime is 641147933. The reversal of 641147921 is 129741146.

It is a cyclic number.

It is not a de Polignac number, because 641147921 - 2² = 641147917 is a prime.

It is a super-2 number, since 2×641147921² = 822141313205244482, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (641147621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 512705 + ... + 513953.

It is an arithmetic number, because the mean of its divisors is an integer number (42900000).

Almost surely, 2^641147921 is an apocalyptic number.

It is an amenable number.

641147921 is a deficient number, since it is larger than the sum of its proper divisors (45252079).

641147921 is a wasteful number, since it uses less digits than its factorization.

641147921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1880.

The product of its digits is 12096, while the sum is 35.

The square root of 641147921 is about 25320.8988979459. The cubic root of 641147921 is about 862.2888017788.

The spelling of 641147921 in words is "six hundred forty-one million, one hundred forty-seven thousand, nine hundred twenty-one".