31144428 has 72 divisors (see below), whose sum is σ = 91259168. Its totient is φ = 8771328.

The previous prime is 31144423. The next prime is 31144441. The reversal of 31144428 is 82444113.

It is not an unprimeable number, because it can be changed into a prime (31144423) 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, 17550 + ... + 19242.

Almost surely, 2^31144428 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 31144428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45629584).

31144428 is an abundant number, since it is smaller than the sum of its proper divisors (60114740).

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

31144428 is a wasteful number, since it uses less digits than its factorization.

31144428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1783 (or 1778 counting only the distinct ones).

The product of its digits is 3072, while the sum is 27.

The square root of 31144428 is about 5580.7193084763. The cubic root of 31144428 is about 314.6251626010.

The spelling of 31144428 in words is "thirty-one million, one hundred forty-four thousand, four hundred twenty-eight".