21152421349 has 2 divisors, whose sum is σ = 21152421350. Its totient is φ = 21152421348.

The previous prime is 21152421341. The next prime is 21152421383. The reversal of 21152421349 is 94312425112.

It is an a-pointer prime, because the next prime (21152421383) can be obtained adding 21152421349 to its sum of digits (34).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20809505025 + 342916324 = 144255^2 + 18518^2 .

It is a cyclic number.

It is not a de Polignac number, because 21152421349 - 2³ = 21152421341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21152421341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10576210674 + 10576210675.

It is an arithmetic number, because the mean of its divisors is an integer number (10576210675).

Almost surely, 2^21152421349 is an apocalyptic number.

It is an amenable number.

21152421349 is a deficient number, since it is larger than the sum of its proper divisors (1).

21152421349 is an equidigital number, since it uses as much as digits as its factorization.

21152421349 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17280, while the sum is 34.

The spelling of 21152421349 in words is "twenty-one billion, one hundred fifty-two million, four hundred twenty-one thousand, three hundred forty-nine".