641367636 has 96 divisors (see below), whose sum is σ = 1950278400. Its totient is φ = 159197184.

The previous prime is 641367631. The next prime is 641367641. The reversal of 641367636 is 636763146.

It is an interprime number because it is at equal distance from previous prime (641367631) and next prime (641367641).

It is a super-2 number, since 2×641367636² = 822704889016456992, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

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 (641367631) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1290 + ... + 35838.

It is an arithmetic number, because the mean of its divisors is an integer number (20315400).

Almost surely, 2^641367636 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 641367636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (975139200).

641367636 is an abundant number, since it is smaller than the sum of its proper divisors (1308910764).

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

641367636 is a wasteful number, since it uses less digits than its factorization.

641367636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34593 (or 34591 counting only the distinct ones).

The product of its digits is 326592, while the sum is 42.

The square root of 641367636 is about 25325.2371361060. The cubic root of 641367636 is about 862.3872897877.

The spelling of 641367636 in words is "six hundred forty-one million, three hundred sixty-seven thousand, six hundred thirty-six".