21793812387 has 8 divisors (see below), whose sum is σ = 29060109504. Its totient is φ = 14528361768.

The previous prime is 21793812379. The next prime is 21793812407. The reversal of 21793812387 is 78321839712.

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

It is not a de Polignac number, because 21793812387 - 2³ = 21793812379 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21793812377) 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, 148893 + ... + 256430.

It is an arithmetic number, because the mean of its divisors is an integer number (3632513688).

Almost surely, 2^21793812387 is an apocalyptic number.

21793812387 is a deficient number, since it is larger than the sum of its proper divisors (7266297117).

21793812387 is a wasteful number, since it uses less digits than its factorization.

21793812387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 423249.

The product of its digits is 1016064, while the sum is 51.

The spelling of 21793812387 in words is "twenty-one billion, seven hundred ninety-three million, eight hundred twelve thousand, three hundred eighty-seven".