1125642791 has 16 divisors (see below), whose sum is σ = 1386202944. Its totient is φ = 890106624.

The previous prime is 1125642787. The next prime is 1125642851. The reversal of 1125642791 is 1972465211.

It is a cyclic number.

It is not a de Polignac number, because 1125642791 - 2² = 1125642787 is a prime.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1125642731) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 274331 + ... + 278403.

It is an arithmetic number, because the mean of its divisors is an integer number (86637684).

Almost surely, 2^1125642791 is an apocalyptic number.

1125642791 is a deficient number, since it is larger than the sum of its proper divisors (260560153).

1125642791 is a wasteful number, since it uses less digits than its factorization.

1125642791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7130.

The product of its digits is 30240, while the sum is 38.

The square root of 1125642791 is about 33550.6004566237. The cubic root of 1125642791 is about 1040.2399566504.

The spelling of 1125642791 in words is "one billion, one hundred twenty-five million, six hundred forty-two thousand, seven hundred ninety-one".