21113794405 has 16 divisors (see below), whose sum is σ = 27950443200. Its totient is φ = 15182949760.

The previous prime is 21113794399. The next prime is 21113794411. The reversal of 21113794405 is 50449731112.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21113794399) and next prime (21113794411).

It is a de Polignac number, because none of the positive numbers 2^k-21113794405 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2151775 + ... + 2161564.

It is an arithmetic number, because the mean of its divisors is an integer number (1746902700).

Almost surely, 2^21113794405 is an apocalyptic number.

It is an amenable number.

21113794405 is a deficient number, since it is larger than the sum of its proper divisors (6836648795).

21113794405 is a wasteful number, since it uses less digits than its factorization.

21113794405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4313444.

The product of its (nonzero) digits is 30240, while the sum is 37.

It can be divided in two parts, 21113 and 794405, that added together give a palindrome (815518).

The spelling of 21113794405 in words is "twenty-one billion, one hundred thirteen million, seven hundred ninety-four thousand, four hundred five".