1331988 has 48 divisors (see below), whose sum is σ = 3609984. Its totient is φ = 374400.

The previous prime is 1331987. The next prime is 1331989. The reversal of 1331988 is 8891331.

It is an interprime number because it is at equal distance from previous prime (1331987) and next prime (1331989).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331987) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8406 + ... + 8562.

It is an arithmetic number, because the mean of its divisors is an integer number (75208).

2^1331988 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1331988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1804992).

1331988 is an abundant number, since it is smaller than the sum of its proper divisors (2277996).

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

1331988 is a wasteful number, since it uses less digits than its factorization.

1331988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272 (or 270 counting only the distinct ones).

The product of its digits is 5184, while the sum is 33.

The square root of 1331988 is about 1154.1178449361. The cubic root of 1331988 is about 110.0272108991.

The spelling of 1331988 in words is "one million, three hundred thirty-one thousand, nine hundred eighty-eight".