21210311313 has 12 divisors (see below), whose sum is σ = 30741683700. Its totient is φ = 14091945696.

The previous prime is 21210311303. The next prime is 21210311357. The reversal of 21210311313 is 31311301212.

21210311313 is a `hidden beast` number, since 21 + 21 + 0 + 311 + 313 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 14541465744 + 6668845569 = 120588^2 + 81663^2 .

It is not a de Polignac number, because 21210311313 - 2²¹ = 21208214161 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21210311303) 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 in 11 ways as a sum of consecutive naturals, for example, 4019038 + ... + 4024311.

It is an arithmetic number, because the mean of its divisors is an integer number (2561806975).

Almost surely, 2^21210311313 is an apocalyptic number.

It is an amenable number.

21210311313 is a deficient number, since it is larger than the sum of its proper divisors (9531372387).

21210311313 is a wasteful number, since it uses less digits than its factorization.

21210311313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8043648 (or 8043645 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 21210311313 its reverse (31311301212), we get a palindrome (52521612525).

The spelling of 21210311313 in words is "twenty-one billion, two hundred ten million, three hundred eleven thousand, three hundred thirteen".