21864227873 has 4 divisors (see below), whose sum is σ = 21864650820. Its totient is φ = 21863804928.

The previous prime is 21864227857. The next prime is 21864227911. The reversal of 21864227873 is 37872246812.

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

It can be written as a sum of positive squares in 2 ways, for example, as 3995756944 + 17868470929 = 63212^2 + 133673^2 .

It is a cyclic number.

It is not a de Polignac number, because 21864227873 - 2⁴ = 21864227857 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21864227813) 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, 121040 + ... + 241617.

It is an arithmetic number, because the mean of its divisors is an integer number (5466162705).

Almost surely, 2^21864227873 is an apocalyptic number.

It is an amenable number.

21864227873 is a deficient number, since it is larger than the sum of its proper divisors (422947).

21864227873 is an equidigital number, since it uses as much as digits as its factorization.

21864227873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422946.

The product of its digits is 1806336, while the sum is 50.

The spelling of 21864227873 in words is "twenty-one billion, eight hundred sixty-four million, two hundred twenty-seven thousand, eight hundred seventy-three".