2638281988 has 6 divisors (see below), whose sum is σ = 4616993486. Its totient is φ = 1319140992.

The previous prime is 2638281983. The next prime is 2638282013. The reversal of 2638281988 is 8891828362.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1645275844 + 993006144 = 40562^2 + 31512^2 .

It is not an unprimeable number, because it can be changed into a prime (2638281983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 329785245 + ... + 329785252.

Almost surely, 2^2638281988 is an apocalyptic number.

It is an amenable number.

2638281988 is a deficient number, since it is larger than the sum of its proper divisors (1978711498).

2638281988 is a wasteful number, since it uses less digits than its factorization.

2638281988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659570501 (or 659570499 counting only the distinct ones).

The product of its digits is 2654208, while the sum is 55.

The square root of 2638281988 is about 51364.2092122521. The cubic root of 2638281988 is about 1381.7847781666.

The spelling of 2638281988 in words is "two billion, six hundred thirty-eight million, two hundred eighty-one thousand, nine hundred eighty-eight".