21634688347 has 8 divisors (see below), whose sum is σ = 22196087280. Its totient is φ = 21079779840.

The previous prime is 21634688303. The next prime is 21634688377. The reversal of 21634688347 is 74388643612.

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-21634688347 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21634688294 and 21634688303.

It is not an unprimeable number, because it can be changed into a prime (21634688377) 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, 1615854 + ... + 1629187.

It is an arithmetic number, because the mean of its divisors is an integer number (2774510910).

Almost surely, 2^21634688347 is an apocalyptic number.

21634688347 is a deficient number, since it is larger than the sum of its proper divisors (561398933).

21634688347 is a wasteful number, since it uses less digits than its factorization.

21634688347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3245213.

The product of its digits is 4644864, while the sum is 52.

The spelling of 21634688347 in words is "twenty-one billion, six hundred thirty-four million, six hundred eighty-eight thousand, three hundred forty-seven".