31031442 has 54 divisors (see below), whose sum is σ = 73532511. Its totient is φ = 9453600.

The previous prime is 31031431. The next prime is 31031449. The reversal of 31031442 is 24413013.

31031442 is a `hidden beast` number, since 310 + 314 + 42 = 666.

It can be written as a sum of positive squares in 5 ways, for example, as 21427641 + 9603801 = 4629^2 + 3099^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=3939.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (31031449) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 307192 + ... + 307292.

Almost surely, 2^31031442 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31031442

31031442 is an abundant number, since it is smaller than the sum of its proper divisors (42501069).

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

31031442 is a wasteful number, since it uses less digits than its factorization.

31031442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 31031442 is about 5570.5872221876. The cubic root of 31031442 is about 314.2442350414.

Multiplying 31031442 by its sum of digits (18), we get a square (558565956 = 23634²).

31031442 divided by its sum of digits (18) gives a square (1723969 = 1313²).

Multiplying 31031442 by its product of nonzero digits (288), we get a square (8937055296 = 94536²).

Adding to 31031442 its reverse (24413013), we get a palindrome (55444455).

The spelling of 31031442 in words is "thirty-one million, thirty-one thousand, four hundred forty-two".