1115217989 has 4 divisors (see below), whose sum is σ = 1123241280. Its totient is φ = 1107194700.

The previous prime is 1115217973. The next prime is 1115217991. The reversal of 1115217989 is 9897125111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9897125111 = 1367 ⋅7240033.

It is a cyclic number.

It is not a de Polignac number, because 1115217989 - 2⁴ = 1115217973 is a prime.

It is a super-2 number, since 2×1115217989² = 2487422325978408242, 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 (1115217889) 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, 4011437 + ... + 4011714.

It is an arithmetic number, because the mean of its divisors is an integer number (280810320).

Almost surely, 2^1115217989 is an apocalyptic number.

It is an amenable number.

1115217989 is a deficient number, since it is larger than the sum of its proper divisors (8023291).

1115217989 is an equidigital number, since it uses as much as digits as its factorization.

1115217989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8023290.

The product of its digits is 45360, while the sum is 44.

The square root of 1115217989 is about 33394.8796823705. The cubic root of 1115217989 is about 1037.0187020802.

The spelling of 1115217989 in words is "one billion, one hundred fifteen million, two hundred seventeen thousand, nine hundred eighty-nine".