641236860 has 216 divisors, whose sum is σ = 2199073968. Its totient is φ = 149990400.

The previous prime is 641236853. The next prime is 641236873. The reversal of 641236860 is 68632146.

641236860 is a `hidden beast` number, since 641 + 2 + 3 + 6 + 8 + 6 + 0 = 666.

It is a super-2 number, since 2×641236860² = 822369421245319200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1902612 + ... + 1902948.

It is an arithmetic number, because the mean of its divisors is an integer number (10180898).

Almost surely, 2^641236860 is an apocalyptic number.

641236860 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 641236860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1099536984).

641236860 is an abundant number, since it is smaller than the sum of its proper divisors (1557837108).

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

641236860 is a wasteful number, since it uses less digits than its factorization.

641236860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425 (or 389 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 641236860 is about 25322.6550740636. The cubic root of 641236860 is about 862.3286717034.

The spelling of 641236860 in words is "six hundred forty-one million, two hundred thirty-six thousand, eight hundred sixty".