21227104391 has 4 divisors (see below), whose sum is σ = 21319799400. Its totient is φ = 21134409384.

The previous prime is 21227104357. The next prime is 21227104427. The reversal of 21227104391 is 19340172212.

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 21227104391 - 2¹⁴ = 21227088007 is a prime.

It is a super-2 number, since 2×21227104391² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21227104091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46347161 + ... + 46347618.

It is an arithmetic number, because the mean of its divisors is an integer number (5329949850).

Almost surely, 2^21227104391 is an apocalyptic number.

21227104391 is a deficient number, since it is larger than the sum of its proper divisors (92695009).

21227104391 is an equidigital number, since it uses as much as digits as its factorization.

21227104391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92695008.

The product of its (nonzero) digits is 6048, while the sum is 32.

The spelling of 21227104391 in words is "twenty-one billion, two hundred twenty-seven million, one hundred four thousand, three hundred ninety-one".