1251163213 has 2 divisors, whose sum is σ = 1251163214. Its totient is φ = 1251163212.

The previous prime is 1251163189. The next prime is 1251163231. The reversal of 1251163213 is 3123611521.

It is a happy number.

Together with next prime (1251163231) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 814645764 + 436517449 = 28542^2 + 20893^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1251163213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1251163273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625581606 + 625581607.

It is an arithmetic number, because the mean of its divisors is an integer number (625581607).

Almost surely, 2^1251163213 is an apocalyptic number.

It is an amenable number.

1251163213 is a deficient number, since it is larger than the sum of its proper divisors (1).

1251163213 is an equidigital number, since it uses as much as digits as its factorization.

1251163213 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1080, while the sum is 25.

The square root of 1251163213 is about 35371.7855500680. The cubic root of 1251163213 is about 1077.5513836138.

Adding to 1251163213 its reverse (3123611521), we get a palindrome (4374774734).

The spelling of 1251163213 in words is "one billion, two hundred fifty-one million, one hundred sixty-three thousand, two hundred thirteen".