641456738 has 12 divisors (see below), whose sum is σ = 1041893298. Its totient is φ = 296056800.

The previous prime is 641456719. The next prime is 641456741. The reversal of 641456738 is 837654146.

It can be written as a sum of positive squares in 3 ways, for example, as 202009369 + 439447369 = 14213^2 + 20963^2 .

It is a super-2 number, since 2×641456738² = 822933493451201288, which contains 22 as substring.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 948563 + ... + 949238.

Almost surely, 2^641456738 is an apocalyptic number.

641456738 is a deficient number, since it is larger than the sum of its proper divisors (400436560).

641456738 is a wasteful number, since it uses less digits than its factorization.

641456738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1897829 (or 1897816 counting only the distinct ones).

The product of its digits is 483840, while the sum is 44.

The square root of 641456738 is about 25326.9962293202. The cubic root of 641456738 is about 862.4272236571.

The spelling of 641456738 in words is "six hundred forty-one million, four hundred fifty-six thousand, seven hundred thirty-eight".