3638405520 has 320 divisors, whose sum is σ = 13145825280. Its totient is φ = 923788800.

The previous prime is 3638405509. The next prime is 3638405539. The reversal of 3638405520 is 255048363.

It is a happy number.

3638405520 is a `hidden beast` number, since 3 + 63 + 8 + 40 + 552 + 0 = 666.

3638405520 is digitally balanced in base 2, because in such base 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 (36).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4485915 + ... + 4486725.

It is an arithmetic number, because the mean of its divisors is an integer number (41080704).

Almost surely, 2^3638405520 is an apocalyptic number.

3638405520 is a gapful number since it is divisible by the number (30) 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 3638405520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6572912640).

3638405520 is an abundant number, since it is smaller than the sum of its proper divisors (9507419760).

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

3638405520 is a wasteful number, since it uses less digits than its factorization.

3638405520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 931 (or 919 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 3638405520 is about 60319.1969442565. The cubic root of 3638405520 is about 1538.0496927999.

The spelling of 3638405520 in words is "three billion, six hundred thirty-eight million, four hundred five thousand, five hundred twenty".