21122111047 has 2 divisors, whose sum is σ = 21122111048. Its totient is φ = 21122111046.

The previous prime is 21122111009. The next prime is 21122111089. The reversal of 21122111047 is 74011122112.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21122111047 - 2²⁷ = 20987893319 is a prime.

It is a super-2 number, since 2×21122111047² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21122111447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561055523 + 10561055524.

It is an arithmetic number, because the mean of its divisors is an integer number (10561055524).

Almost surely, 2^21122111047 is an apocalyptic number.

21122111047 is a deficient number, since it is larger than the sum of its proper divisors (1).

21122111047 is an equidigital number, since it uses as much as digits as its factorization.

21122111047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 224, while the sum is 22.

Adding to 21122111047 its reverse (74011122112), we get a palindrome (95133233159).

The spelling of 21122111047 in words is "twenty-one billion, one hundred twenty-two million, one hundred eleven thousand, forty-seven".