21112012069 has 2 divisors, whose sum is σ = 21112012070. Its totient is φ = 21112012068.

The previous prime is 21112012049. The next prime is 21112012147. The reversal of 21112012069 is 96021021112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17008072225 + 4103939844 = 130415^2 + 64062^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112012069 - 2²³ = 21103623461 is a prime.

It is a super-2 number, since 2×21112012069² (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 (21112012049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556006034 + 10556006035.

It is an arithmetic number, because the mean of its divisors is an integer number (10556006035).

Almost surely, 2^21112012069 is an apocalyptic number.

It is an amenable number.

21112012069 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112012069 is an equidigital number, since it uses as much as digits as its factorization.

21112012069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 25.

The spelling of 21112012069 in words is "twenty-one billion, one hundred twelve million, twelve thousand, sixty-nine".