21230544263993 has 2 divisors, whose sum is σ = 21230544263994. Its totient is φ = 21230544263992.

The previous prime is 21230544263947. The next prime is 21230544264019. The reversal of 21230544263993 is 39936244503212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17263468234489 + 3967076029504 = 4154933^2 + 1991752^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21230544263993 is a prime.

It is not a weakly prime, because it can be changed into another prime (21230544260993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10615272131996 + 10615272131997.

It is an arithmetic number, because the mean of its divisors is an integer number (10615272131997).

Almost surely, 2^{21230544263993} is an apocalyptic number.

It is an amenable number.

21230544263993 is a deficient number, since it is larger than the sum of its proper divisors (1).

21230544263993 is an equidigital number, since it uses as much as digits as its factorization.

21230544263993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8398080, while the sum is 53.

The spelling of 21230544263993 in words is "twenty-one trillion, two hundred thirty billion, five hundred forty-four million, two hundred sixty-three thousand, nine hundred ninety-three".