21694831573 has 8 divisors (see below), whose sum is σ = 21724236416. Its totient is φ = 21665448000.

The previous prime is 21694831547. The next prime is 21694831603. The reversal of 21694831573 is 37513849612.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21694831573 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21694834573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3204490 + ... + 3211252.

It is an arithmetic number, because the mean of its divisors is an integer number (2715529552).

Almost surely, 2^21694831573 is an apocalyptic number.

It is an amenable number.

21694831573 is a deficient number, since it is larger than the sum of its proper divisors (29404843).

21694831573 is a wasteful number, since it uses less digits than its factorization.

21694831573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10635.

The product of its digits is 1088640, while the sum is 49.

The spelling of 21694831573 in words is "twenty-one billion, six hundred ninety-four million, eight hundred thirty-one thousand, five hundred seventy-three".