2638874681 has 4 divisors (see below), whose sum is σ = 2647470672. Its totient is φ = 2630278692.

The previous prime is 2638874671. The next prime is 2638874687. The reversal of 2638874681 is 1864788362.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2638874681 - 2²⁶ = 2571765817 is a prime.

It is a super-2 number, since 2×2638874681² = 13927319164045703522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2638874687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4297535 + ... + 4298148.

It is an arithmetic number, because the mean of its divisors is an integer number (661867668).

Almost surely, 2^2638874681 is an apocalyptic number.

It is an amenable number.

2638874681 is a deficient number, since it is larger than the sum of its proper divisors (8595991).

2638874681 is an equidigital number, since it uses as much as digits as its factorization.

2638874681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8595990.

The product of its digits is 3096576, while the sum is 53.

The square root of 2638874681 is about 51369.9784017864. The cubic root of 2638874681 is about 1381.8882435846. Note that the first 3 decimals are identical.

The spelling of 2638874681 in words is "two billion, six hundred thirty-eight million, eight hundred seventy-four thousand, six hundred eighty-one".