18836737921 has 8 divisors (see below), whose sum is σ = 19829744000. Its totient is φ = 17843891760.

The previous prime is 18836737891. The next prime is 18836737951. The reversal of 18836737921 is 12973763881.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (18836737891) and next prime (18836737951).

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18836737921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18836737951) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 259336 + ... + 323926.

It is an arithmetic number, because the mean of its divisors is an integer number (2478718000).

Almost surely, 2^18836737921 is an apocalyptic number.

It is an amenable number.

18836737921 is a deficient number, since it is larger than the sum of its proper divisors (993006079).

18836737921 is a wasteful number, since it uses less digits than its factorization.

18836737921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79959.

The product of its digits is 3048192, while the sum is 55.

The spelling of 18836737921 in words is "eighteen billion, eight hundred thirty-six million, seven hundred thirty-seven thousand, nine hundred twenty-one".