1311988 has 24 divisors (see below), whose sum is σ = 2465120. Its totient is φ = 609120.

The previous prime is 1311971. The next prime is 1311991. The reversal of 1311988 is 8891131.

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, 4495 + ... + 4777.

2^1311988 is an apocalyptic number.

It is an amenable number.

1311988 is a deficient number, since it is larger than the sum of its proper divisors (1153132).

1311988 is a wasteful number, since it uses less digits than its factorization.

1311988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 367 (or 365 counting only the distinct ones).

The product of its digits is 1728, while the sum is 31.

The square root of 1311988 is about 1145.4204468229. The cubic root of 1311988 is about 109.4737397325.

The spelling of 1311988 in words is "one million, three hundred eleven thousand, nine hundred eighty-eight".