21387856283 has 4 divisors (see below), whose sum is σ = 21394612800. Its totient is φ = 21381099768.

The previous prime is 21387856229. The next prime is 21387856297. The reversal of 21387856283 is 38265878312.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21387856283 - 2¹⁰ = 21387855259 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21387846283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3373508 + ... + 3379841.

It is an arithmetic number, because the mean of its divisors is an integer number (5348653200).

Almost surely, 2^21387856283 is an apocalyptic number.

21387856283 is a deficient number, since it is larger than the sum of its proper divisors (6756517).

21387856283 is an equidigital number, since it uses as much as digits as its factorization.

21387856283 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6756516.

The product of its digits is 3870720, while the sum is 53.

The spelling of 21387856283 in words is "twenty-one billion, three hundred eighty-seven million, eight hundred fifty-six thousand, two hundred eighty-three".