21706872366 has 16 divisors (see below), whose sum is σ = 43426944000. Its totient is φ = 7233424248.

The previous prime is 21706872353. The next prime is 21706872367. The reversal of 21706872366 is 66327860712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21706872367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 528526 + ... + 568113.

It is an arithmetic number, because the mean of its divisors is an integer number (2714184000).

Almost surely, 2^21706872366 is an apocalyptic number.

21706872366 is an abundant number, since it is smaller than the sum of its proper divisors (21720071634).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21706872366 is a wasteful number, since it uses less digits than its factorization.

21706872366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1099943.

The product of its (nonzero) digits is 1016064, while the sum is 48.

The spelling of 21706872366 in words is "twenty-one billion, seven hundred six million, eight hundred seventy-two thousand, three hundred sixty-six".