21287688395 has 8 divisors (see below), whose sum is σ = 25550197200. Its totient is φ = 17026836640.

The previous prime is 21287688379. The next prime is 21287688451. The reversal of 21287688395 is 59388678212.

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

It is not a de Polignac number, because 21287688395 - 2⁴ = 21287688379 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 385820 + ... + 437529.

It is an arithmetic number, because the mean of its divisors is an integer number (3193774650).

Almost surely, 2^21287688395 is an apocalyptic number.

21287688395 is a deficient number, since it is larger than the sum of its proper divisors (4262508805).

21287688395 is an equidigital number, since it uses as much as digits as its factorization.

21287688395 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 828525.

The product of its digits is 11612160, while the sum is 59.

The spelling of 21287688395 in words is "twenty-one billion, two hundred eighty-seven million, six hundred eighty-eight thousand, three hundred ninety-five".