21126504717 has 12 divisors (see below), whose sum is σ = 30517522464. Its totient is φ = 14083662600.

The previous prime is 21126504713. The next prime is 21126504731. The reversal of 21126504717 is 71740562112.

21126504717 is a `hidden beast` number, since 21 + 126 + 504 + 7 + 1 + 7 = 666.

It is not a de Polignac number, because 21126504717 - 2² = 21126504713 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21126504713) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 207592 + ... + 292142.

It is an arithmetic number, because the mean of its divisors is an integer number (2543126872).

Almost surely, 2^21126504717 is an apocalyptic number.

It is an amenable number.

21126504717 is a deficient number, since it is larger than the sum of its proper divisors (9391017747).

21126504717 is a wasteful number, since it uses less digits than its factorization.

21126504717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112320 (or 112317 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 36.

The spelling of 21126504717 in words is "twenty-one billion, one hundred twenty-six million, five hundred four thousand, seven hundred seventeen".