21856887323 has 2 divisors, whose sum is σ = 21856887324. Its totient is φ = 21856887322.

The previous prime is 21856887317. The next prime is 21856887347. The reversal of 21856887323 is 32378865812.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21856887323 - 2¹⁴ = 21856870939 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21856887313) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10928443661 + 10928443662.

It is an arithmetic number, because the mean of its divisors is an integer number (10928443662).

Almost surely, 2^21856887323 is an apocalyptic number.

21856887323 is a deficient number, since it is larger than the sum of its proper divisors (1).

21856887323 is an equidigital number, since it uses as much as digits as its factorization.

21856887323 is an evil number, because the sum of its binary digits is even.

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

The spelling of 21856887323 in words is "twenty-one billion, eight hundred fifty-six million, eight hundred eighty-seven thousand, three hundred twenty-three".