18947631844739 has 4 divisors (see below), whose sum is σ = 20405141986656. Its totient is φ = 17490121702824.

The previous prime is 18947631844723. The next prime is 18947631844741. The reversal of 18947631844739 is 93744813674981.

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 18947631844739 - 2⁴ = 18947631844723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18947631844639) 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, 728755070939 + ... + 728755070964.

It is an arithmetic number, because the mean of its divisors is an integer number (5101285496664).

Almost surely, 2^{18947631844739} is an apocalyptic number.

18947631844739 is a deficient number, since it is larger than the sum of its proper divisors (1457510141917).

18947631844739 is a wasteful number, since it uses less digits than its factorization.

18947631844739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1457510141916.

The product of its digits is 877879296, while the sum is 74.

The spelling of 18947631844739 in words is "eighteen trillion, nine hundred forty-seven billion, six hundred thirty-one million, eight hundred forty-four thousand, seven hundred thirty-nine".