18013874644 has 12 divisors (see below), whose sum is σ = 31555163668. Its totient is φ = 8998113600.

The previous prime is 18013874623. The next prime is 18013874657. The reversal of 18013874644 is 44647831081.

It can be written as a sum of positive squares in 2 ways, for example, as 15715631044 + 2298243600 = 125362^2 + 47940^2 .

It is a super-2 number, since 2×18013874644² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18013874594 and 18013874603.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2201337 + ... + 2209504.

Almost surely, 2^18013874644 is an apocalyptic number.

It is an amenable number.

18013874644 is a deficient number, since it is larger than the sum of its proper divisors (13541289024).

18013874644 is a wasteful number, since it uses less digits than its factorization.

18013874644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4411866 (or 4411864 counting only the distinct ones).

The product of its (nonzero) digits is 516096, while the sum is 46.

The spelling of 18013874644 in words is "eighteen billion, thirteen million, eight hundred seventy-four thousand, six hundred forty-four".