21313352491 has 2 divisors, whose sum is σ = 21313352492. Its totient is φ = 21313352490.

The previous prime is 21313352453. The next prime is 21313352497. The reversal of 21313352491 is 19425331312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21313352491 - 2¹⁹ = 21312828203 is a prime.

It is not a weakly prime, because it can be changed into another prime (21313352497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10656676245 + 10656676246.

It is an arithmetic number, because the mean of its divisors is an integer number (10656676246).

Almost surely, 2^21313352491 is an apocalyptic number.

21313352491 is a deficient number, since it is larger than the sum of its proper divisors (1).

21313352491 is an equidigital number, since it uses as much as digits as its factorization.

21313352491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19440, while the sum is 34.

The spelling of 21313352491 in words is "twenty-one billion, three hundred thirteen million, three hundred fifty-two thousand, four hundred ninety-one".