1251115279 has 2 divisors, whose sum is σ = 1251115280. Its totient is φ = 1251115278.

The previous prime is 1251115277. The next prime is 1251115301. The reversal of 1251115279 is 9725111521.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1251115279 - 2¹ = 1251115277 is a prime.

Together with 1251115277, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1251115277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625557639 + 625557640.

It is an arithmetic number, because the mean of its divisors is an integer number (625557640).

Almost surely, 2^1251115279 is an apocalyptic number.

1251115279 is a deficient number, since it is larger than the sum of its proper divisors (1).

1251115279 is an equidigital number, since it uses as much as digits as its factorization.

1251115279 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6300, while the sum is 34.

The square root of 1251115279 is about 35371.1079696410. The cubic root of 1251115279 is about 1077.5376225507.

The spelling of 1251115279 in words is "one billion, two hundred fifty-one million, one hundred fifteen thousand, two hundred seventy-nine".