21039240259 has 2 divisors, whose sum is σ = 21039240260. Its totient is φ = 21039240258.

The previous prime is 21039240253. The next prime is 21039240281. The reversal of 21039240259 is 95204293012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21039240259 - 2¹⁵ = 21039207491 is a prime.

It is not a weakly prime, because it can be changed into another prime (21039240253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10519620129 + 10519620130.

It is an arithmetic number, because the mean of its divisors is an integer number (10519620130).

Almost surely, 2^21039240259 is an apocalyptic number.

21039240259 is a deficient number, since it is larger than the sum of its proper divisors (1).

21039240259 is an equidigital number, since it uses as much as digits as its factorization.

21039240259 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 37.

The spelling of 21039240259 in words is "twenty-one billion, thirty-nine million, two hundred forty thousand, two hundred fifty-nine".