5638720881 has 4 divisors (see below), whose sum is σ = 7518294512. Its totient is φ = 3759147252.

The previous prime is 5638720873. The next prime is 5638720891. The reversal of 5638720881 is 1880278365.

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 not a de Polignac number, because 5638720881 - 2³ = 5638720873 is a prime.

It is a super-2 number, since 2×5638720881² = 63590346347650832322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 5638720881.

It is not an unprimeable number, because it can be changed into a prime (5638720811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 939786811 + ... + 939786816.

It is an arithmetic number, because the mean of its divisors is an integer number (1879573628).

Almost surely, 2^5638720881 is an apocalyptic number.

It is an amenable number.

5638720881 is a deficient number, since it is larger than the sum of its proper divisors (1879573631).

5638720881 is a wasteful number, since it uses less digits than its factorization.

5638720881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1879573630.

The product of its (nonzero) digits is 645120, while the sum is 48.

The square root of 5638720881 is about 75091.4168264256. The cubic root of 5638720881 is about 1779.8915139243.

The spelling of 5638720881 in words is "five billion, six hundred thirty-eight million, seven hundred twenty thousand, eight hundred eighty-one".