641605990 has 8 divisors (see below), whose sum is σ = 1154890800. Its totient is φ = 256642392.

The previous prime is 641605981. The next prime is 641606033. The reversal of 641605990 is 99506146.

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

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, 32080290 + ... + 32080309.

It is an arithmetic number, because the mean of its divisors is an integer number (144361350).

Almost surely, 2^641605990 is an apocalyptic number.

641605990 is a deficient number, since it is larger than the sum of its proper divisors (513284810).

641605990 is a wasteful number, since it uses less digits than its factorization.

641605990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64160606.

The product of its (nonzero) digits is 58320, while the sum is 40.

The square root of 641605990 is about 25329.9425581662. The cubic root of 641605990 is about 862.4941073601.

The spelling of 641605990 in words is "six hundred forty-one million, six hundred five thousand, nine hundred ninety".