21152421313 has 2 divisors, whose sum is σ = 21152421314. Its totient is φ = 21152421312.

The previous prime is 21152421307. The next prime is 21152421341. The reversal of 21152421313 is 31312425112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18849093264 + 2303328049 = 137292^2 + 47993^2 .

It is a cyclic number.

It is not a de Polignac number, because 21152421313 - 2⁵ = 21152421281 is a prime.

It is not a weakly prime, because it can be changed into another prime (21152421383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10576210656 + 10576210657.

It is an arithmetic number, because the mean of its divisors is an integer number (10576210657).

Almost surely, 2^21152421313 is an apocalyptic number.

It is an amenable number.

21152421313 is a deficient number, since it is larger than the sum of its proper divisors (1).

21152421313 is an equidigital number, since it uses as much as digits as its factorization.

21152421313 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 25.

Adding to 21152421313 its reverse (31312425112), we get a palindrome (52464846425).

The spelling of 21152421313 in words is "twenty-one billion, one hundred fifty-two million, four hundred twenty-one thousand, three hundred thirteen".