21345320415 has 32 divisors (see below), whose sum is σ = 34374476736. Its totient is φ = 11310279680.

The previous prime is 21345320401. The next prime is 21345320419. The reversal of 21345320415 is 51402354312.

It is not a de Polignac number, because 21345320415 - 2¹⁵ = 21345287647 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21345320419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5958925 + ... + 5962505.

It is an arithmetic number, because the mean of its divisors is an integer number (1074202398).

Almost surely, 2^21345320415 is an apocalyptic number.

21345320415 is a deficient number, since it is larger than the sum of its proper divisors (13029156321).

21345320415 is a wasteful number, since it uses less digits than its factorization.

21345320415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6059.

The product of its (nonzero) digits is 14400, while the sum is 30.

Adding to 21345320415 its reverse (51402354312), we get a palindrome (72747674727).

The spelling of 21345320415 in words is "twenty-one billion, three hundred forty-five million, three hundred twenty thousand, four hundred fifteen".