641399616 has 252 divisors, whose sum is σ = 2175357600. Its totient is φ = 179112960.

The previous prime is 641399611. The next prime is 641399651. The reversal of 641399616 is 616993146.

641399616 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×641399616² = 822786934809894912, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641399611) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1070485 + ... + 1071083.

Almost surely, 2^641399616 is an apocalyptic number.

641399616 is a gapful number since it is divisible by the number (66) 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 641399616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1087678800).

641399616 is an abundant number, since it is smaller than the sum of its proper divisors (1533957984).

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

641399616 is a wasteful number, since it uses less digits than its factorization.

641399616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654 (or 628 counting only the distinct ones).

The product of its digits is 209952, while the sum is 45.

The square root of 641399616 is about 25325.8685142287. The cubic root of 641399616 is about 862.4016230580.

The spelling of 641399616 in words is "six hundred forty-one million, three hundred ninety-nine thousand, six hundred sixteen".