21440467897 has 2 divisors, whose sum is σ = 21440467898. Its totient is φ = 21440467896.

The previous prime is 21440467879. The next prime is 21440467921. The reversal of 21440467897 is 79876404412.

Together with previous prime (21440467879) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20581919296 + 858548601 = 143464^2 + 29301^2 .

It is a cyclic number.

It is not a de Polignac number, because 21440467897 - 2¹⁵ = 21440435129 is a prime.

It is a super-3 number, since 3×21440467897³ (a number of 32 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (21440467297) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10720233948 + 10720233949.

It is an arithmetic number, because the mean of its divisors is an integer number (10720233949).

Almost surely, 2^21440467897 is an apocalyptic number.

It is an amenable number.

21440467897 is a deficient number, since it is larger than the sum of its proper divisors (1).

21440467897 is an equidigital number, since it uses as much as digits as its factorization.

21440467897 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2709504, while the sum is 52.

The spelling of 21440467897 in words is "twenty-one billion, four hundred forty million, four hundred sixty-seven thousand, eight hundred ninety-seven".