21181693117 has 8 divisors (see below), whose sum is σ = 23802839424. Its totient is φ = 18702230448.

The previous prime is 21181693103. The next prime is 21181693121. The reversal of 21181693117 is 71139618112.

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-21181693117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21181693117.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21181693717) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35420593 + ... + 35421190.

It is an arithmetic number, because the mean of its divisors is an integer number (2975354928).

Almost surely, 2^21181693117 is an apocalyptic number.

It is an amenable number.

21181693117 is a deficient number, since it is larger than the sum of its proper divisors (2621146307).

21181693117 is a wasteful number, since it uses less digits than its factorization.

21181693117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70841819.

The product of its digits is 18144, while the sum is 40.

The spelling of 21181693117 in words is "twenty-one billion, one hundred eighty-one million, six hundred ninety-three thousand, one hundred seventeen".