1261130691 has 8 divisors (see below), whose sum is σ = 1681996624. Its totient is φ = 840509280.

The previous prime is 1261130683. The next prime is 1261130797. The reversal of 1261130691 is 1960311621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1261130691 - 2³ = 1261130683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1261130291) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48736 + ... + 69981.

It is an arithmetic number, because the mean of its divisors is an integer number (210249578).

Almost surely, 2^1261130691 is an apocalyptic number.

1261130691 is a deficient number, since it is larger than the sum of its proper divisors (420865933).

1261130691 is a wasteful number, since it uses less digits than its factorization.

1261130691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122261.

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 1261130691 is about 35512.4019322828. The cubic root of 1261130691 is about 1080.4052808514.

The spelling of 1261130691 in words is "one billion, two hundred sixty-one million, one hundred thirty thousand, six hundred ninety-one".