641654378 has 8 divisors (see below), whose sum is σ = 975666468. Its totient is φ = 316432224.

The previous prime is 641654371. The next prime is 641654381. The reversal of 641654378 is 873456146.

It can be written as a sum of positive squares in 2 ways, for example, as 611919169 + 29735209 = 24737^2 + 5453^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (641654371) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2197301 + ... + 2197592.

Almost surely, 2^641654378 is an apocalyptic number.

641654378 is a deficient number, since it is larger than the sum of its proper divisors (334012090).

641654378 is a wasteful number, since it uses less digits than its factorization.

641654378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4394968.

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

The square root of 641654378 is about 25330.8976943179. The cubic root of 641654378 is about 862.5157890549.

The spelling of 641654378 in words is "six hundred forty-one million, six hundred fifty-four thousand, three hundred seventy-eight".