21420212313 has 32 divisors (see below), whose sum is σ = 30542230656. Its totient is φ = 13306216448.

The previous prime is 21420212293. The next prime is 21420212413. The reversal of 21420212313 is 31321202412.

It is a cyclic number.

It is not a de Polignac number, because 21420212313 - 2⁶ = 21420212249 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21420212313.

It is not an unprimeable number, because it can be changed into a prime (21420212413) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7392481 + ... + 7395377.

It is an arithmetic number, because the mean of its divisors is an integer number (954444708).

Almost surely, 2^21420212313 is an apocalyptic number.

It is an amenable number.

21420212313 is a deficient number, since it is larger than the sum of its proper divisors (9122018343).

21420212313 is a wasteful number, since it uses less digits than its factorization.

21420212313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4313.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21420212313 its reverse (31321202412), we get a palindrome (52741414725).

Subtracting 21420212313 from its reverse (31321202412), we obtain a palindrome (9900990099).

The spelling of 21420212313 in words is "twenty-one billion, four hundred twenty million, two hundred twelve thousand, three hundred thirteen".