731988 has 18 divisors (see below), whose sum is σ = 1850394. Its totient is φ = 243984.

The previous prime is 731981. The next prime is 731999. The reversal of 731988 is 889137.

731988 is nontrivially palindromic in base 11.

731988 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 725904 + 6084 = 852^2 + 78^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 20333 = 731988 / (7 + 3 + 1 + 9 + 8 + 8).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (731981) by changing a digit.

731988 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10131 + ... + 10202.

2⁷³¹⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

731988 is an abundant number, since it is smaller than the sum of its proper divisors (1118406).

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

731988 is a wasteful number, since it uses less digits than its factorization.

731988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20343 (or 20338 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 731988 is about 855.5629725508. The cubic root of 731988 is about 90.1227953457.

The spelling of 731988 in words is "seven hundred thirty-one thousand, nine hundred eighty-eight".