21392199457 has 2 divisors, whose sum is σ = 21392199458. Its totient is φ = 21392199456.

The previous prime is 21392199397. The next prime is 21392199463. The reversal of 21392199457 is 75499129312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19496816161 + 1895383296 = 139631^2 + 43536^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21392199457 is a prime.

It is not a weakly prime, because it can be changed into another prime (21392199497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10696099728 + 10696099729.

It is an arithmetic number, because the mean of its divisors is an integer number (10696099729).

Almost surely, 2^21392199457 is an apocalyptic number.

It is an amenable number.

21392199457 is a deficient number, since it is larger than the sum of its proper divisors (1).

21392199457 is an equidigital number, since it uses as much as digits as its factorization.

21392199457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1224720, while the sum is 52.

The spelling of 21392199457 in words is "twenty-one billion, three hundred ninety-two million, one hundred ninety-nine thousand, four hundred fifty-seven".