31304400 has 120 divisors (see below), whose sum is σ = 105633120. Its totient is φ = 7902720.

The previous prime is 31304347. The next prime is 31304401. The reversal of 31304400 is 440313.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 31304400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31304401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22114 + ... + 23486.

It is an arithmetic number, because the mean of its divisors is an integer number (880276).

Almost surely, 2^31304400 is an apocalyptic number.

31304400 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 31304400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52816560).

31304400 is an abundant number, since it is smaller than the sum of its proper divisors (74328720).

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

31304400 is a wasteful number, since it uses less digits than its factorization.

31304400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1413 (or 1402 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 31304400 is about 5595.0335119640. The cubic root of 31304400 is about 315.1629290663.

Adding to 31304400 its reverse (440313), we get a palindrome (31744713).

The spelling of 31304400 in words is "thirty-one million, three hundred four thousand, four hundred".