801618667138 has 4 divisors (see below), whose sum is σ = 1202428000710. Its totient is φ = 400809333568.

The previous prime is 801618667133. The next prime is 801618667141. The reversal of 801618667138 is 831766816108.

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

It can be written as a sum of positive squares in only one way, i.e., 723304323729 + 78314343409 = 850473^2 + 279847^2 .

It is a super-2 number, since 2×801618667138² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (801618667133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200404666783 + ... + 200404666786.

Almost surely, 2^801618667138 is an apocalyptic number.

801618667138 is a deficient number, since it is larger than the sum of its proper divisors (400809333572).

801618667138 is a wasteful number, since it uses less digits than its factorization.

801618667138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400809333571.

The product of its (nonzero) digits is 2322432, while the sum is 55.

The spelling of 801618667138 in words is "eight hundred one billion, six hundred eighteen million, six hundred sixty-seven thousand, one hundred thirty-eight".