111661489 has 3 divisors (see below), whose sum is σ = 111672057. Its totient is φ = 111650922.

The previous prime is 111661471. The next prime is 111661493. The reversal of 111661489 is 984166111.

The square root of 111661489 is 10567.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 984166111 = 18077 ⋅54443.

It is not a de Polignac number, because 111661489 - 2¹⁷ = 111530417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (111661469) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 5284 + ... + 15850.

It is an arithmetic number, because the mean of its divisors is an integer number (37224019).

Almost surely, 2^111661489 is an apocalyptic number.

111661489 is the 10567-th square number.

111661489 is the 5284-th centered octagonal number.

It is an amenable number.

111661489 is a deficient number, since it is larger than the sum of its proper divisors (10568).

111661489 is an frugal number, since it uses more digits than its factorization.

111661489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21134 (or 10567 counting only the distinct ones).

The product of its digits is 10368, while the sum is 37.

The cubic root of 111661489 is about 481.5423319971.

The spelling of 111661489 in words is "one hundred eleven million, six hundred sixty-one thousand, four hundred eighty-nine".