641540444 has 12 divisors (see below), whose sum is σ = 1133596464. Its totient is φ = 317655744.

The previous prime is 641540413. The next prime is 641540531. The reversal of 641540444 is 444045146.

It is a self number, because there is not a number n which added to its sum of digits gives 641540444.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 778157 + ... + 778980.

It is an arithmetic number, because the mean of its divisors is an integer number (94466372).

Almost surely, 2^641540444 is an apocalyptic number.

It is an amenable number.

641540444 is a deficient number, since it is larger than the sum of its proper divisors (492056020).

641540444 is a wasteful number, since it uses less digits than its factorization.

641540444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1557244 (or 1557242 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 32.

The square root of 641540444 is about 25328.6486808910. The cubic root of 641540444 is about 862.4647357703.

The spelling of 641540444 in words is "six hundred forty-one million, five hundred forty thousand, four hundred forty-four".