5131511231666 has 4 divisors (see below), whose sum is σ = 7697266847502. Its totient is φ = 2565755615832.

The previous prime is 5131511231663. The next prime is 5131511231683. The reversal of 5131511231666 is 6661321151315.

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., 4522363762225 + 609147469441 = 2126585^2 + 780479^2 .

It is a super-2 number, since 2×5131511231666² (a number of 26 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (5131511231663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1282877807915 + ... + 1282877807918.

Almost surely, 2^{5131511231666} is an apocalyptic number.

5131511231666 is a deficient number, since it is larger than the sum of its proper divisors (2565755615836).

5131511231666 is a wasteful number, since it uses less digits than its factorization.

5131511231666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2565755615835.

The product of its digits is 97200, while the sum is 41.

The spelling of 5131511231666 in words is "five trillion, one hundred thirty-one billion, five hundred eleven million, two hundred thirty-one thousand, six hundred sixty-six".