21823131991547 has 2 divisors, whose sum is σ = 21823131991548. Its totient is φ = 21823131991546.

The previous prime is 21823131991487. The next prime is 21823131991579. The reversal of 21823131991547 is 74519913132812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21823131991547 - 2²² = 21823127797243 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21823131991492 and 21823131991501.

It is not a weakly prime, because it can be changed into another prime (21823131991147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10911565995773 + 10911565995774.

It is an arithmetic number, because the mean of its divisors is an integer number (10911565995774).

Almost surely, 2^{21823131991547} is an apocalyptic number.

21823131991547 is a deficient number, since it is larger than the sum of its proper divisors (1).

21823131991547 is an equidigital number, since it uses as much as digits as its factorization.

21823131991547 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3265920, while the sum is 56.

The spelling of 21823131991547 in words is "twenty-one trillion, eight hundred twenty-three billion, one hundred thirty-one million, nine hundred ninety-one thousand, five hundred forty-seven".