18244643544 has 96 divisors (see below), whose sum is σ = 49698230400. Its totient is φ = 6046502400.

The previous prime is 18244643507. The next prime is 18244643551. The reversal of 18244643544 is 44534644281.

It is a happy number.

18244643544 is a `hidden beast` number, since 1 + 8 + 2 + 44 + 64 + 3 + 544 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 18244643544.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12677977 + ... + 12679415.

It is an arithmetic number, because the mean of its divisors is an integer number (517689900).

Almost surely, 2^18244643544 is an apocalyptic number.

It is an amenable number.

18244643544 is an abundant number, since it is smaller than the sum of its proper divisors (31453586856).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18244643544 is a wasteful number, since it uses less digits than its factorization.

18244643544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2345 (or 2338 counting only the distinct ones).

The product of its digits is 1474560, while the sum is 45.

The spelling of 18244643544 in words is "eighteen billion, two hundred forty-four million, six hundred forty-three thousand, five hundred forty-four".