18642914639 has 4 divisors (see below), whose sum is σ = 18852385680. Its totient is φ = 18433443600.

The previous prime is 18642914617. The next prime is 18642914651. The reversal of 18642914639 is 93641924681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93641924681 = 3413 ⋅27436837.

It is a cyclic number.

It is not a de Polignac number, because 18642914639 - 2¹⁶ = 18642849103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18642914699) 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, 104735387 + ... + 104735564.

It is an arithmetic number, because the mean of its divisors is an integer number (4713096420).

Almost surely, 2^18642914639 is an apocalyptic number.

18642914639 is a deficient number, since it is larger than the sum of its proper divisors (209471041).

18642914639 is an equidigital number, since it uses as much as digits as its factorization.

18642914639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209471040.

The product of its digits is 2239488, while the sum is 53.

The spelling of 18642914639 in words is "eighteen billion, six hundred forty-two million, nine hundred fourteen thousand, six hundred thirty-nine".