18720244158663 has 16 divisors (see below), whose sum is σ = 25676097753600. Its totient is φ = 12124823901120.

The previous prime is 18720244158659. The next prime is 18720244158691. The reversal of 18720244158663 is 36685144202781.

It is not a de Polignac number, because 18720244158663 - 2² = 18720244158659 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18720244158643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 318374593 + ... + 318433386.

It is an arithmetic number, because the mean of its divisors is an integer number (1604756109600).

Almost surely, 2^{18720244158663} is an apocalyptic number.

18720244158663 is a deficient number, since it is larger than the sum of its proper divisors (6955853594937).

18720244158663 is a wasteful number, since it uses less digits than its factorization.

18720244158663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 636808262.

The product of its (nonzero) digits is 15482880, while the sum is 57.

The spelling of 18720244158663 in words is "eighteen trillion, seven hundred twenty billion, two hundred forty-four million, one hundred fifty-eight thousand, six hundred sixty-three".