2638401551 has 4 divisors (see below), whose sum is σ = 2674544112. Its totient is φ = 2602258992.

The previous prime is 2638401431. The next prime is 2638401569. The reversal of 2638401551 is 1551048362.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2638401551 is a prime.

It is a super-2 number, since 2×2638401551² = 13922325488638411202, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2638401151) 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, 18071171 + ... + 18071316.

It is an arithmetic number, because the mean of its divisors is an integer number (668636028).

Almost surely, 2^2638401551 is an apocalyptic number.

2638401551 is a deficient number, since it is larger than the sum of its proper divisors (36142561).

2638401551 is an equidigital number, since it uses as much as digits as its factorization.

2638401551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36142560.

The product of its (nonzero) digits is 28800, while the sum is 35.

The square root of 2638401551 is about 51365.3730736963. The cubic root of 2638401551 is about 1381.8056513256.

The spelling of 2638401551 in words is "two billion, six hundred thirty-eight million, four hundred one thousand, five hundred fifty-one".