2638934640 has 200 divisors, whose sum is σ = 9195951600. Its totient is φ = 701374464.

The previous prime is 2638934621. The next prime is 2638934677. The reversal of 2638934640 is 464398362.

2638934640 is a `hidden beast` number, since 2 + 638 + 9 + 3 + 4 + 6 + 4 + 0 = 666.

2638934640 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2909067 + ... + 2909973.

It is an arithmetic number, because the mean of its divisors is an integer number (45979758).

Almost surely, 2^2638934640 is an apocalyptic number.

2638934640 is a gapful number since it is divisible by the number (20) 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 2638934640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4597975800).

2638934640 is an abundant number, since it is smaller than the sum of its proper divisors (6557016960).

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

2638934640 is a wasteful number, since it uses less digits than its factorization.

2638934640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1381 (or 1366 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 45.

The square root of 2638934640 is about 51370.5619980938. The cubic root of 2638934640 is about 1381.8987096632.

The spelling of 2638934640 in words is "two billion, six hundred thirty-eight million, nine hundred thirty-four thousand, six hundred forty".