641740788 has 54 divisors (see below), whose sum is σ = 1748454162. Its totient is φ = 197290080.

The previous prime is 641740787. The next prime is 641740793. The reversal of 641740788 is 887047146.

It can be written as a sum of positive squares in only one way, i.e., 444282084 + 197458704 = 21078^2 + 14052^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641740783) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 547443 + ... + 548613.

Almost surely, 2^641740788 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 641740788, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (874227081).

641740788 is an abundant number, since it is smaller than the sum of its proper divisors (1106713374).

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

641740788 is a wasteful number, since it uses less digits than its factorization.

641740788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2365 (or 1189 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 45.

The square root of 641740788 is about 25332.6032614100. The cubic root of 641740788 is about 862.5545049361.

The spelling of 641740788 in words is "six hundred forty-one million, seven hundred forty thousand, seven hundred eighty-eight".