1109890261 has 2 divisors, whose sum is σ = 1109890262. Its totient is φ = 1109890260.

The previous prime is 1109890259. The next prime is 1109890283. The reversal of 1109890261 is 1620989011.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1109289636 + 600625 = 33306^2 + 775^2 .

It is a cyclic number.

It is not a de Polignac number, because 1109890261 - 2¹ = 1109890259 is a prime.

Together with 1109890259, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 1109890261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1109890361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 554945130 + 554945131.

It is an arithmetic number, because the mean of its divisors is an integer number (554945131).

Almost surely, 2^1109890261 is an apocalyptic number.

It is an amenable number.

1109890261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1109890261 is an equidigital number, since it uses as much as digits as its factorization.

1109890261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 37.

The square root of 1109890261 is about 33315.0155485481. The cubic root of 1109890261 is about 1035.3646831138.

The spelling of 1109890261 in words is "one billion, one hundred nine million, eight hundred ninety thousand, two hundred sixty-one".