641988456 has 32 divisors (see below), whose sum is σ = 1612181760. Its totient is φ = 213034752.

The previous prime is 641988449. The next prime is 641988467. The reversal of 641988456 is 654889146.

It is a junction number, because it is equal to n+sod(n) for n = 641988399 and 641988408.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54625 + ... + 65328.

It is an arithmetic number, because the mean of its divisors is an integer number (50380680).

Almost surely, 2^641988456 is an apocalyptic number.

It is an amenable number.

641988456 is an abundant number, since it is smaller than the sum of its proper divisors (970193304).

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

641988456 is a wasteful number, since it uses less digits than its factorization.

641988456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120185 (or 120181 counting only the distinct ones).

The product of its digits is 1658880, while the sum is 51.

The square root of 641988456 is about 25337.4911149466. The cubic root of 641988456 is about 862.6654529893.

The spelling of 641988456 in words is "six hundred forty-one million, nine hundred eighty-eight thousand, four hundred fifty-six".