21936039893 has 2 divisors, whose sum is σ = 21936039894. Its totient is φ = 21936039892.

The previous prime is 21936039887. The next prime is 21936039967. The reversal of 21936039893 is 39893063912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14719027684 + 7217012209 = 121322^2 + 84953^2 .

It is a cyclic number.

It is not a de Polignac number, because 21936039893 - 2¹⁸ = 21935777749 is a prime.

It is a super-3 number, since 3×21936039893³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21936039863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10968019946 + 10968019947.

It is an arithmetic number, because the mean of its divisors is an integer number (10968019947).

Almost surely, 2^21936039893 is an apocalyptic number.

It is an amenable number.

21936039893 is a deficient number, since it is larger than the sum of its proper divisors (1).

21936039893 is an equidigital number, since it uses as much as digits as its factorization.

21936039893 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1889568, while the sum is 53.

The spelling of 21936039893 in words is "twenty-one billion, nine hundred thirty-six million, thirty-nine thousand, eight hundred ninety-three".