21415521313 has 4 divisors (see below), whose sum is σ = 21615666480. Its totient is φ = 21215376148.

The previous prime is 21415521311. The next prime is 21415521359. The reversal of 21415521313 is 31312551412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21415521313 - 2¹ = 21415521311 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21415521311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100072423 + ... + 100072636.

It is an arithmetic number, because the mean of its divisors is an integer number (5403916620).

Almost surely, 2^21415521313 is an apocalyptic number.

It is an amenable number.

21415521313 is a deficient number, since it is larger than the sum of its proper divisors (200145167).

21415521313 is a wasteful number, since it uses less digits than its factorization.

21415521313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200145166.

The product of its digits is 3600, while the sum is 28.

The spelling of 21415521313 in words is "twenty-one billion, four hundred fifteen million, five hundred twenty-one thousand, three hundred thirteen".