21354311315 has 16 divisors (see below), whose sum is σ = 25712214048. Its totient is φ = 17025524736.

The previous prime is 21354311273. The next prime is 21354311339. The reversal of 21354311315 is 51311345312.

It is a cyclic number.

It is not a de Polignac number, because 21354311315 - 2¹⁴ = 21354294931 is a prime.

It is a super-2 number, since 2×21354311315² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1832387 + ... + 1844003.

It is an arithmetic number, because the mean of its divisors is an integer number (1607013378).

Almost surely, 2^21354311315 is an apocalyptic number.

21354311315 is a deficient number, since it is larger than the sum of its proper divisors (4357902733).

21354311315 is a wasteful number, since it uses less digits than its factorization.

21354311315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12838.

The product of its digits is 5400, while the sum is 29.

Adding to 21354311315 its reverse (51311345312), we get a palindrome (72665656627).

The spelling of 21354311315 in words is "twenty-one billion, three hundred fifty-four million, three hundred eleven thousand, three hundred fifteen".