641769657 has 16 divisors (see below), whose sum is σ = 885960192. Its totient is φ = 412796160.

The previous prime is 641769649. The next prime is 641769659. The reversal of 641769657 is 756967146.

It is a happy number.

It is not a de Polignac number, because 641769657 - 2³ = 641769649 is a prime.

It is not an unprimeable number, because it can be changed into a prime (641769659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21103 + ... + 41579.

It is an arithmetic number, because the mean of its divisors is an integer number (55372512).

Almost surely, 2^641769657 is an apocalyptic number.

It is an amenable number.

641769657 is a deficient number, since it is larger than the sum of its proper divisors (244190535).

641769657 is a wasteful number, since it uses less digits than its factorization.

641769657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20848.

The product of its digits is 1905120, while the sum is 51.

The square root of 641769657 is about 25333.1730543175. The cubic root of 641769657 is about 862.5674388772.

The spelling of 641769657 in words is "six hundred forty-one million, seven hundred sixty-nine thousand, six hundred fifty-seven".