31040000 has 100 divisors (see below), whose sum is σ = 78298374. Its totient is φ = 12288000.

The previous prime is 31039991. The next prime is 31040017. The reversal of 31040000 is 4013.

It can be written as a sum of positive squares in 5 ways, for example, as 215296 + 30824704 = 464^2 + 5552^2 .

It is a tau number, because it is divible by the number of its divisors (100).

It is a Harshad number since it is a multiple of its sum of digits (8).

It is a self number, because there is not a number n which added to its sum of digits gives 31040000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 319952 + ... + 320048.

Almost surely, 2^31040000 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 31040000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39149187).

31040000 is an abundant number, since it is smaller than the sum of its proper divisors (47258374).

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

31040000 is an frugal number, since it uses more digits than its factorization.

31040000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 8.

The square root of 31040000 is about 5571.3553108736. The cubic root of 31040000 is about 314.2731203139.

Adding to 31040000 its reverse (4013), we get a palindrome (31044013).

The spelling of 31040000 in words is "thirty-one million, forty thousand".