783641664 has 168 divisors, whose sum is σ = 2434828760. Its totient is φ = 239542272.

The previous prime is 783641659. The next prime is 783641711. The reversal of 783641664 is 466146387.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 296115264 + 487526400 = 17208^2 + 22080^2 .

It is a super-2 number, since 2×783641664² = 1228188515113377792, 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 23 ways as a sum of consecutive naturals, for example, 1714524 + ... + 1714980.

Almost surely, 2^783641664 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 783641664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1217414380).

783641664 is an abundant number, since it is smaller than the sum of its proper divisors (1651187096).

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

783641664 is a wasteful number, since it uses less digits than its factorization.

783641664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 717 (or 704 counting only the distinct ones).

The product of its digits is 580608, while the sum is 45.

The square root of 783641664 is about 27993.6004115226. The cubic root of 783641664 is about 921.9467535593.

The spelling of 783641664 in words is "seven hundred eighty-three million, six hundred forty-one thousand, six hundred sixty-four".