21420322313 has 4 divisors (see below), whose sum is σ = 23068039428. Its totient is φ = 19772605200.

The previous prime is 21420322307. The next prime is 21420322321. The reversal of 21420322313 is 31322302412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6888502009 + 14531820304 = 82997^2 + 120548^2 .

It is a cyclic number.

It is not a de Polignac number, because 21420322313 - 2⁶ = 21420322249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21420322513) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 823858538 + ... + 823858563.

It is an arithmetic number, because the mean of its divisors is an integer number (5767009857).

Almost surely, 2^21420322313 is an apocalyptic number.

It is an amenable number.

21420322313 is a deficient number, since it is larger than the sum of its proper divisors (1647717115).

21420322313 is a wasteful number, since it uses less digits than its factorization.

21420322313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1647717114.

The product of its (nonzero) digits is 1728, while the sum is 23.

Adding to 21420322313 its reverse (31322302412), we get a palindrome (52742624725).

The spelling of 21420322313 in words is "twenty-one billion, four hundred twenty million, three hundred twenty-two thousand, three hundred thirteen".