21723280793 has 2 divisors, whose sum is σ = 21723280794. Its totient is φ = 21723280792.

The previous prime is 21723280753. The next prime is 21723280807. The reversal of 21723280793 is 39708232712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17733716224 + 3989564569 = 133168^2 + 63163^2 .

It is a cyclic number.

It is not a de Polignac number, because 21723280793 - 2³⁰ = 20649538969 is a prime.

It is not a weakly prime, because it can be changed into another prime (21723280753) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10861640396 + 10861640397.

It is an arithmetic number, because the mean of its divisors is an integer number (10861640397).

Almost surely, 2^21723280793 is an apocalyptic number.

It is an amenable number.

21723280793 is a deficient number, since it is larger than the sum of its proper divisors (1).

21723280793 is an equidigital number, since it uses as much as digits as its factorization.

21723280793 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 254016, while the sum is 44.

The spelling of 21723280793 in words is "twenty-one billion, seven hundred twenty-three million, two hundred eighty thousand, seven hundred ninety-three".