2638404720 has 120 divisors (see below), whose sum is σ = 10126467936. Its totient is φ = 603062784.

The previous prime is 2638404697. The next prime is 2638404721. The reversal of 2638404720 is 274048362.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×2638404720² = 13922358933036556800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2638404721) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 256707 + ... + 266786.

Almost surely, 2^2638404720 is an apocalyptic number.

2638404720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2638404720 is an abundant number, since it is smaller than the sum of its proper divisors (7488063216).

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

2638404720 is a wasteful number, since it uses less digits than its factorization.

2638404720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 523519 (or 523510 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 36.

The square root of 2638404720 is about 51365.4039213165. The cubic root of 2638404720 is about 1381.8062045571.

The spelling of 2638404720 in words is "two billion, six hundred thirty-eight million, four hundred four thousand, seven hundred twenty".