641955825 has 72 divisors (see below), whose sum is σ = 1326069888. Its totient is φ = 290787840.

The previous prime is 641955791. The next prime is 641955851. The reversal of 641955825 is 528559146.

641955825 is a `hidden beast` number, since 64 + 1 + 9 + 5 + 582 + 5 = 666.

It is not a de Polignac number, because 641955825 - 2⁹ = 641955313 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 176172 + ... + 179778.

Almost surely, 2^641955825 is an apocalyptic number.

It is an amenable number.

641955825 is an abundant number, since it is smaller than the sum of its proper divisors (684114063).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

641955825 is a wasteful number, since it uses less digits than its factorization.

641955825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3743 (or 3735 counting only the distinct ones).

The product of its digits is 432000, while the sum is 45.

The square root of 641955825 is about 25336.8471795525. The cubic root of 641955825 is about 862.6508368836.

The spelling of 641955825 in words is "six hundred forty-one million, nine hundred fifty-five thousand, eight hundred twenty-five".