11681998 has 16 divisors (see below), whose sum is σ = 18562320. Its totient is φ = 5498496.

The previous prime is 11681981. The next prime is 11682023. The reversal of 11681998 is 89918611.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5686 + ... + 7462.

It is an arithmetic number, because the mean of its divisors is an integer number (1160145).

Almost surely, 2^11681998 is an apocalyptic number.

11681998 is a deficient number, since it is larger than the sum of its proper divisors (6880322).

11681998 is a wasteful number, since it uses less digits than its factorization.

11681998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1971.

The product of its digits is 31104, while the sum is 43.

The square root of 11681998 is about 3417.8937958924. The cubic root of 11681998 is about 226.9023754302.

The spelling of 11681998 in words is "eleven million, six hundred eighty-one thousand, nine hundred ninety-eight".