1115071261 has 4 divisors (see below), whose sum is σ = 1115198172. Its totient is φ = 1114944352.

The previous prime is 1115071249. The next prime is 1115071273. The reversal of 1115071261 is 1621705111.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (1115071249) and next prime (1115071273).

It can be written as a sum of positive squares in 2 ways, for example, as 476548900 + 638522361 = 21830^2 + 25269^2 .

It is a cyclic number.

It is not a de Polignac number, because 1115071261 - 2⁵ = 1115071229 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1115071201) 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, 49210 + ... + 68203.

It is an arithmetic number, because the mean of its divisors is an integer number (278799543).

Almost surely, 2^1115071261 is an apocalyptic number.

It is an amenable number.

1115071261 is a deficient number, since it is larger than the sum of its proper divisors (126911).

1115071261 is an equidigital number, since it uses as much as digits as its factorization.

1115071261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126910.

The product of its (nonzero) digits is 420, while the sum is 25.

The square root of 1115071261 is about 33392.6827463742. The cubic root of 1115071261 is about 1036.9732202834.

Adding to 1115071261 its reverse (1621705111), we get a palindrome (2736776372).

The spelling of 1115071261 in words is "one billion, one hundred fifteen million, seventy-one thousand, two hundred sixty-one".