1251131867 has 4 divisors (see below), whose sum is σ = 1251213600. Its totient is φ = 1251050136.

The previous prime is 1251131863. The next prime is 1251131879. The reversal of 1251131867 is 7681311521.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1251131867 - 2² = 1251131863 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1251131863) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10268 + ... + 51065.

It is an arithmetic number, because the mean of its divisors is an integer number (312803400).

Almost surely, 2^1251131867 is an apocalyptic number.

1251131867 is a deficient number, since it is larger than the sum of its proper divisors (81733).

1251131867 is an equidigital number, since it uses as much as digits as its factorization.

1251131867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81732.

The product of its digits is 10080, while the sum is 35.

The square root of 1251131867 is about 35371.3424540263. The cubic root of 1251131867 is about 1077.5423847325.

The spelling of 1251131867 in words is "one billion, two hundred fifty-one million, one hundred thirty-one thousand, eight hundred sixty-seven".