11897989 has 4 divisors (see below), whose sum is σ = 12093100. Its totient is φ = 11702880.

The previous prime is 11897957. The next prime is 11897993. The reversal of 11897989 is 98979811.

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 708964 + 11189025 = 842^2 + 3345^2 .

It is a cyclic number.

It is not a de Polignac number, because 11897989 - 2⁵ = 11897957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11897939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97464 + ... + 97585.

It is an arithmetic number, because the mean of its divisors is an integer number (3023275).

Almost surely, 2^11897989 is an apocalyptic number.

It is an amenable number.

11897989 is a deficient number, since it is larger than the sum of its proper divisors (195111).

11897989 is an equidigital number, since it uses as much as digits as its factorization.

11897989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195110.

The product of its digits is 326592, while the sum is 52.

The square root of 11897989 is about 3449.3461699284. The cubic root of 11897989 is about 228.2922601217.

The spelling of 11897989 in words is "eleven million, eight hundred ninety-seven thousand, nine hundred eighty-nine".