31381056 has 168 divisors, whose sum is σ = 105769664. Its totient is φ = 8709120.

The previous prime is 31381043. The next prime is 31381061. The reversal of 31381056 is 65018313.

It is a tau number, because it is divible by the number of its divisors (168).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 173286 + ... + 173466.

Almost surely, 2^31381056 is an apocalyptic number.

31381056 is a gapful number since it is divisible by the number (36) 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 31381056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52884832).

31381056 is an abundant number, since it is smaller than the sum of its proper divisors (74388608).

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

31381056 is a wasteful number, since it uses less digits than its factorization.

31381056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249 (or 236 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 31381056 is about 5601.8796845345. The cubic root of 31381056 is about 315.4199689345.

Adding to 31381056 its reverse (65018313), we get a palindrome (96399369).

The spelling of 31381056 in words is "thirty-one million, three hundred eighty-one thousand, fifty-six".