31998000 has 80 divisors (see below), whose sum is σ = 103180896. Its totient is φ = 8531200.

The previous prime is 31997989. The next prime is 31998073. The reversal of 31998000 is 89913.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3334 + ... + 8666.

Almost surely, 2^31998000 is an apocalyptic number.

31998000 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31998000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51590448).

31998000 is an abundant number, since it is smaller than the sum of its proper divisors (71182896).

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

31998000 is a wasteful number, since it uses less digits than its factorization.

31998000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5359 (or 5343 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 31998000 is about 5656.6774700349. The cubic root of 31998000 is about 317.4735960848.

The spelling of 31998000 in words is "thirty-one million, nine hundred ninety-eight thousand".