21722517347 has 4 divisors (see below), whose sum is σ = 21722927760. Its totient is φ = 21722106936.

The previous prime is 21722517319. The next prime is 21722517361. The reversal of 21722517347 is 74371522712.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21722517347 - 2²⁶ = 21655408483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21722517307) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111572 + ... + 236417.

It is an arithmetic number, because the mean of its divisors is an integer number (5430731940).

Almost surely, 2^21722517347 is an apocalyptic number.

21722517347 is a deficient number, since it is larger than the sum of its proper divisors (410413).

21722517347 is an equidigital number, since it uses as much as digits as its factorization.

21722517347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410412.

The product of its digits is 164640, while the sum is 41.

The spelling of 21722517347 in words is "twenty-one billion, seven hundred twenty-two million, five hundred seventeen thousand, three hundred forty-seven".