6638075137 has 4 divisors (see below), whose sum is σ = 6638309716. Its totient is φ = 6637840560.

The previous prime is 6638075113. The next prime is 6638075173. The reversal of 6638075137 is 7315708366.

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

It can be written as a sum of positive squares in 2 ways, for example, as 3095920881 + 3542154256 = 55641^2 + 59516^2 .

It is a cyclic number.

It is not a de Polignac number, because 6638075137 - 2¹¹ = 6638073089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6638075107) 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, 67914 + ... + 133747.

It is an arithmetic number, because the mean of its divisors is an integer number (1659577429).

Almost surely, 2^6638075137 is an apocalyptic number.

It is an amenable number.

6638075137 is a deficient number, since it is larger than the sum of its proper divisors (234579).

6638075137 is a wasteful number, since it uses less digits than its factorization.

6638075137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234578.

The product of its (nonzero) digits is 635040, while the sum is 46.

The square root of 6638075137 is about 81474.3833177030. The cubic root of 6638075137 is about 1879.3776362478.

The spelling of 6638075137 in words is "six billion, six hundred thirty-eight million, seventy-five thousand, one hundred thirty-seven".