21938273293 has 2 divisors, whose sum is σ = 21938273294. Its totient is φ = 21938273292.

The previous prime is 21938273239. The next prime is 21938273309. The reversal of 21938273293 is 39237283912.

Together with previous prime (21938273239) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21904888009 + 33385284 = 148003^2 + 5778^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21938273293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21938273213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10969136646 + 10969136647.

It is an arithmetic number, because the mean of its divisors is an integer number (10969136647).

Almost surely, 2^21938273293 is an apocalyptic number.

It is an amenable number.

21938273293 is a deficient number, since it is larger than the sum of its proper divisors (1).

21938273293 is an equidigital number, since it uses as much as digits as its factorization.

21938273293 is an evil number, because the sum of its binary digits is even.

The product of its digits is 979776, while the sum is 49.

The spelling of 21938273293 in words is "twenty-one billion, nine hundred thirty-eight million, two hundred seventy-three thousand, two hundred ninety-three".