21426898069 has 2 divisors, whose sum is σ = 21426898070. Its totient is φ = 21426898068.

The previous prime is 21426898043. The next prime is 21426898201. The reversal of 21426898069 is 96089862412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15162967044 + 6263931025 = 123138^2 + 79145^2 .

It is a cyclic number.

It is not a de Polignac number, because 21426898069 - 2⁷ = 21426897941 is a prime.

It is a super-2 number, since 2×21426898069² (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 (21426898019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10713449034 + 10713449035.

It is an arithmetic number, because the mean of its divisors is an integer number (10713449035).

Almost surely, 2^21426898069 is an apocalyptic number.

It is an amenable number.

21426898069 is a deficient number, since it is larger than the sum of its proper divisors (1).

21426898069 is an equidigital number, since it uses as much as digits as its factorization.

21426898069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2985984, while the sum is 55.

The spelling of 21426898069 in words is "twenty-one billion, four hundred twenty-six million, eight hundred ninety-eight thousand, sixty-nine".