21623522184749 has 2 divisors, whose sum is σ = 21623522184750. Its totient is φ = 21623522184748.

The previous prime is 21623522184739. The next prime is 21623522184751. The reversal of 21623522184749 is 94748122532612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18919411626025 + 2704110558724 = 4349645^2 + 1644418^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21623522184749 is a prime.

Together with 21623522184751, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21623522184694 and 21623522184703.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21623522184739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10811761092374 + 10811761092375.

It is an arithmetic number, because the mean of its divisors is an integer number (10811761092375).

Almost surely, 2^{21623522184749} is an apocalyptic number.

It is an amenable number.

21623522184749 is a deficient number, since it is larger than the sum of its proper divisors (1).

21623522184749 is an equidigital number, since it uses as much as digits as its factorization.

21623522184749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11612160, while the sum is 56.

The spelling of 21623522184749 in words is "twenty-one trillion, six hundred twenty-three billion, five hundred twenty-two million, one hundred eighty-four thousand, seven hundred forty-nine".