1191988 has 12 divisors (see below), whose sum is σ = 2384032. Its totient is φ = 510840.

The previous prime is 1191979. The next prime is 1191991. The reversal of 1191988 is 8891911.

It is a happy number.

1191988 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21258 + ... + 21313.

2^1191988 is an apocalyptic number.

It is an amenable number.

1191988 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1191988 is a wasteful number, since it uses less digits than its factorization.

1191988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42582 (or 42580 counting only the distinct ones).

The product of its digits is 5184, while the sum is 37.

The square root of 1191988 is about 1091.7820295279. The cubic root of 1191988 is about 106.0288280438.

The spelling of 1191988 in words is "one million, one hundred ninety-one thousand, nine hundred eighty-eight".