21311340415 has 8 divisors (see below), whose sum is σ = 25595052048. Its totient is φ = 17034776640.

The previous prime is 21311340409. The next prime is 21311340433. The reversal of 21311340415 is 51404311312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-21311340415 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21311340415.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1780401 + ... + 1792330.

It is an arithmetic number, because the mean of its divisors is an integer number (3199381506).

Almost surely, 2^21311340415 is an apocalyptic number.

21311340415 is a deficient number, since it is larger than the sum of its proper divisors (4283711633).

21311340415 is a wasteful number, since it uses less digits than its factorization.

21311340415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3573929.

The product of its (nonzero) digits is 1440, while the sum is 25.

Adding to 21311340415 its reverse (51404311312), we get a palindrome (72715651727).

The spelling of 21311340415 in words is "twenty-one billion, three hundred eleven million, three hundred forty thousand, four hundred fifteen".