21347428667 has 8 divisors (see below), whose sum is σ = 21908047200. Its totient is φ = 20793605760.

The previous prime is 21347428589. The next prime is 21347428741. The reversal of 21347428667 is 76682474312.

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

It is a cyclic number.

It is not a de Polignac number, because 21347428667 - 2¹⁴ = 21347412283 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21347428367) 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, 1692542 + ... + 1705107.

It is an arithmetic number, because the mean of its divisors is an integer number (2738505900).

Almost surely, 2^21347428667 is an apocalyptic number.

21347428667 is a deficient number, since it is larger than the sum of its proper divisors (560618533).

21347428667 is a wasteful number, since it uses less digits than its factorization.

21347428667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3397813.

The product of its digits is 2709504, while the sum is 50.

The spelling of 21347428667 in words is "twenty-one billion, three hundred forty-seven million, four hundred twenty-eight thousand, six hundred sixty-seven".