1113561161 has 4 divisors (see below), whose sum is σ = 1131816324. Its totient is φ = 1095306000.

The previous prime is 1113561157. The next prime is 1113561173. The reversal of 1113561161 is 1611653111.

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

It can be written as a sum of positive squares in 2 ways, for example, as 618765625 + 494795536 = 24875^2 + 22244^2 .

It is a cyclic number.

It is not a de Polignac number, because 1113561161 - 2² = 1113561157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1113561161.

It is not an unprimeable number, because it can be changed into a prime (1113561191) 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, 9127490 + ... + 9127611.

It is an arithmetic number, because the mean of its divisors is an integer number (282954081).

Almost surely, 2^1113561161 is an apocalyptic number.

It is an amenable number.

1113561161 is a deficient number, since it is larger than the sum of its proper divisors (18255163).

1113561161 is an equidigital number, since it uses as much as digits as its factorization.

1113561161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18255162.

The product of its digits is 540, while the sum is 26.

The square root of 1113561161 is about 33370.0638447097. The cubic root of 1113561161 is about 1036.5048972437.

The spelling of 1113561161 in words is "one billion, one hundred thirteen million, five hundred sixty-one thousand, one hundred sixty-one".