1261616113 has 4 divisors (see below), whose sum is σ = 1262056000. Its totient is φ = 1261176228.

The previous prime is 1261616107. The next prime is 1261616119. The reversal of 1261616113 is 3116161621.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (1261616107) and next prime (1261616119).

It is a cyclic number.

It is not a de Polignac number, because 1261616113 - 2²⁹ = 724745201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1261616119) 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, 215613 + ... + 221386.

It is an arithmetic number, because the mean of its divisors is an integer number (315514000).

Almost surely, 2^1261616113 is an apocalyptic number.

It is an amenable number.

1261616113 is a deficient number, since it is larger than the sum of its proper divisors (439887).

1261616113 is an equidigital number, since it uses as much as digits as its factorization.

1261616113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 439886.

The product of its digits is 1296, while the sum is 28.

The square root of 1261616113 is about 35519.2358166670. The cubic root of 1261616113 is about 1080.5438827217.

Adding to 1261616113 its reverse (3116161621), we get a palindrome (4377777734).

The spelling of 1261616113 in words is "one billion, two hundred sixty-one million, six hundred sixteen thousand, one hundred thirteen".