21924748991 has 2 divisors, whose sum is σ = 21924748992. Its totient is φ = 21924748990.

The previous prime is 21924748961. The next prime is 21924748997. The reversal of 21924748991 is 19984742912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21924748991 - 2⁶ = 21924748927 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21924748997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10962374495 + 10962374496.

It is an arithmetic number, because the mean of its divisors is an integer number (10962374496).

Almost surely, 2^21924748991 is an apocalyptic number.

21924748991 is a deficient number, since it is larger than the sum of its proper divisors (1).

21924748991 is an equidigital number, since it uses as much as digits as its factorization.

21924748991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2612736, while the sum is 56.

The spelling of 21924748991 in words is "twenty-one billion, nine hundred twenty-four million, seven hundred forty-eight thousand, nine hundred ninety-one".