18673951631 has 4 divisors (see below), whose sum is σ = 19772419392. Its totient is φ = 17575483872.

The previous prime is 18673951607. The next prime is 18673951633. The reversal of 18673951631 is 13615937681.

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

It is a cyclic number.

It is not a de Polignac number, because 18673951631 - 2⁶ = 18673951567 is a prime.

It is a super-2 number, since 2×18673951631² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18673951631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18673951633) 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, 549233855 + ... + 549233888.

It is an arithmetic number, because the mean of its divisors is an integer number (4943104848).

Almost surely, 2^18673951631 is an apocalyptic number.

18673951631 is a deficient number, since it is larger than the sum of its proper divisors (1098467761).

18673951631 is a wasteful number, since it uses less digits than its factorization.

18673951631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1098467760.

The product of its digits is 816480, while the sum is 50.

The spelling of 18673951631 in words is "eighteen billion, six hundred seventy-three million, nine hundred fifty-one thousand, six hundred thirty-one".