21142501249 has 2 divisors, whose sum is σ = 21142501250. Its totient is φ = 21142501248.

The previous prime is 21142501229. The next prime is 21142501279. The reversal of 21142501249 is 94210524112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19447697025 + 1694804224 = 139455^2 + 41168^2 .

It is a cyclic number.

It is not a de Polignac number, because 21142501249 - 2⁵ = 21142501217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21142501249.

It is not a weakly prime, because it can be changed into another prime (21142501229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571250624 + 10571250625.

It is an arithmetic number, because the mean of its divisors is an integer number (10571250625).

Almost surely, 2^21142501249 is an apocalyptic number.

It is an amenable number.

21142501249 is a deficient number, since it is larger than the sum of its proper divisors (1).

21142501249 is an equidigital number, since it uses as much as digits as its factorization.

21142501249 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5760, while the sum is 31.

The spelling of 21142501249 in words is "twenty-one billion, one hundred forty-two million, five hundred one thousand, two hundred forty-nine".