21718646433 has 24 divisors (see below), whose sum is σ = 34537314240. Its totient is φ = 13042049760.

The previous prime is 21718646431. The next prime is 21718646491. The reversal of 21718646433 is 33464681712.

21718646433 is a `hidden beast` number, since 2 + 1 + 7 + 186 + 464 + 3 + 3 = 666.

It is not a de Polignac number, because 21718646433 - 2¹ = 21718646431 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21718646431) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 995541 + ... + 1017122.

It is an arithmetic number, because the mean of its divisors is an integer number (1439054760).

Almost surely, 2^21718646433 is an apocalyptic number.

It is an amenable number.

21718646433 is a deficient number, since it is larger than the sum of its proper divisors (12818667807).

21718646433 is a wasteful number, since it uses less digits than its factorization.

21718646433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2012789 (or 2012786 counting only the distinct ones).

The product of its digits is 580608, while the sum is 45.

The spelling of 21718646433 in words is "twenty-one billion, seven hundred eighteen million, six hundred forty-six thousand, four hundred thirty-three".