21120243139 has 2 divisors, whose sum is σ = 21120243140. Its totient is φ = 21120243138.

The previous prime is 21120243091. The next prime is 21120243149. The reversal of 21120243139 is 93134202112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21120243139 - 2³³ = 12530308547 is a prime.

It is not a weakly prime, because it can be changed into another prime (21120243149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560121569 + 10560121570.

It is an arithmetic number, because the mean of its divisors is an integer number (10560121570).

Almost surely, 2^21120243139 is an apocalyptic number.

21120243139 is a deficient number, since it is larger than the sum of its proper divisors (1).

21120243139 is an equidigital number, since it uses as much as digits as its factorization.

21120243139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 28.

The spelling of 21120243139 in words is "twenty-one billion, one hundred twenty million, two hundred forty-three thousand, one hundred thirty-nine".