1251279163 has 4 divisors (see below), whose sum is σ = 1257209608. Its totient is φ = 1245348720.

The previous prime is 1251279151. The next prime is 1251279191. The reversal of 1251279163 is 3619721521.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1251279163 - 2¹³ = 1251270971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1251279103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2964906 + ... + 2965327.

It is an arithmetic number, because the mean of its divisors is an integer number (314302402).

Almost surely, 2^1251279163 is an apocalyptic number.

1251279163 is a deficient number, since it is larger than the sum of its proper divisors (5930445).

1251279163 is an equidigital number, since it uses as much as digits as its factorization.

1251279163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5930444.

The product of its digits is 22680, while the sum is 37.

The square root of 1251279163 is about 35373.4245302883. The cubic root of 1251279163 is about 1077.5846694985.

The spelling of 1251279163 in words is "one billion, two hundred fifty-one million, two hundred seventy-nine thousand, one hundred sixty-three".