31318272 has 144 divisors (see below), whose sum is σ = 97130880. Its totient is φ = 9934848.

The previous prime is 31318247. The next prime is 31318291. The reversal of 31318272 is 27281313.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×31318272² = 1961668322131968, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 158878 + ... + 159074.

It is an arithmetic number, because the mean of its divisors is an integer number (674520).

Almost surely, 2^31318272 is an apocalyptic number.

31318272 is a gapful number since it is divisible by the number (32) 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 31318272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48565440).

31318272 is an abundant number, since it is smaller than the sum of its proper divisors (65812608).

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

31318272 is a wasteful number, since it uses less digits than its factorization.

31318272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245 (or 225 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 31318272 is about 5596.2730455188. The cubic root of 31318272 is about 315.2094751805.

Adding to 31318272 its reverse (27281313), we get a palindrome (58599585).

The spelling of 31318272 in words is "thirty-one million, three hundred eighteen thousand, two hundred seventy-two".