1123090861 has 4 divisors (see below), whose sum is σ = 1123600572. Its totient is φ = 1122581152.

The previous prime is 1123090853. The next prime is 1123090867. The reversal of 1123090861 is 1680903211.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1680903211 = 13 ⋅129300247.

It can be written as a sum of positive squares in 2 ways, for example, as 1080436900 + 42653961 = 32870^2 + 6531^2 .

It is a cyclic number.

It is not a de Polignac number, because 1123090861 - 2³ = 1123090853 is a prime.

It is a super-2 number, since 2×1123090861² = 2522666164123442642, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1123090867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 251536 + ... + 255961.

It is an arithmetic number, because the mean of its divisors is an integer number (280900143).

Almost surely, 2^1123090861 is an apocalyptic number.

It is an amenable number.

1123090861 is a deficient number, since it is larger than the sum of its proper divisors (509711).

1123090861 is an equidigital number, since it uses as much as digits as its factorization.

1123090861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 509710.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 1123090861 is about 33512.5478142143. The cubic root of 1123090861 is about 1039.4532570601.

The spelling of 1123090861 in words is "one billion, one hundred twenty-three million, ninety thousand, eight hundred sixty-one".