21345250139 has 2 divisors, whose sum is σ = 21345250140. Its totient is φ = 21345250138.

The previous prime is 21345250117. The next prime is 21345250163. The reversal of 21345250139 is 93105254312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21345250139 - 2¹⁶ = 21345184603 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21345250099 and 21345250108.

It is not a weakly prime, because it can be changed into another prime (21345250109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10672625069 + 10672625070.

It is an arithmetic number, because the mean of its divisors is an integer number (10672625070).

Almost surely, 2^21345250139 is an apocalyptic number.

21345250139 is a deficient number, since it is larger than the sum of its proper divisors (1).

21345250139 is an equidigital number, since it uses as much as digits as its factorization.

21345250139 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32400, while the sum is 35.

The spelling of 21345250139 in words is "twenty-one billion, three hundred forty-five million, two hundred fifty thousand, one hundred thirty-nine".