18702659921 has 8 divisors (see below), whose sum is σ = 21289984704. Its totient is φ = 16263182320.

The previous prime is 18702659893. The next prime is 18702659947. The reversal of 18702659921 is 12995620781.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-18702659921 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18702659921.

It is not an unprimeable number, because it can be changed into a prime (18702659971) 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 7 ways as a sum of consecutive naturals, for example, 36961526 + ... + 36962031.

It is an arithmetic number, because the mean of its divisors is an integer number (2661248088).

Almost surely, 2^18702659921 is an apocalyptic number.

18702659921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18702659921 is a deficient number, since it is larger than the sum of its proper divisors (2587324783).

18702659921 is a wasteful number, since it uses less digits than its factorization.

18702659921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73923591.

The product of its (nonzero) digits is 544320, while the sum is 50.

The spelling of 18702659921 in words is "eighteen billion, seven hundred two million, six hundred fifty-nine thousand, nine hundred twenty-one".