641231840 has 48 divisors (see below), whose sum is σ = 1604029392. Its totient is φ = 241403904.

The previous prime is 641231839. The next prime is 641231863. The reversal of 641231840 is 48132146.

It is a super-2 number, since 2×641231840² = 822356545259571200, which contains 22 as substring.

It is a congruent number.

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, 115154 + ... + 120593.

It is an arithmetic number, because the mean of its divisors is an integer number (33417279).

Almost surely, 2^641231840 is an apocalyptic number.

It is an amenable number.

641231840 is an abundant number, since it is smaller than the sum of its proper divisors (962797552).

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

641231840 is a wasteful number, since it uses less digits than its factorization.

641231840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235779 (or 235771 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 641231840 is about 25322.5559531419. Note that the first 3 decimals coincide. The cubic root of 641231840 is about 862.3264214163.

Adding to 641231840 its reverse (48132146), we get a palindrome (689363986).

The spelling of 641231840 in words is "six hundred forty-one million, two hundred thirty-one thousand, eight hundred forty".