31378228 has 18 divisors (see below), whose sum is σ = 63877506. Its totient is φ = 13447728.

The previous prime is 31378223. The next prime is 31378307. The reversal of 31378228 is 82287313.

It can be written as a sum of positive squares in only one way, i.e., 17405584 + 13972644 = 4172^2 + 3738^2 .

It is a junction number, because it is equal to n+sod(n) for n = 31378193 and 31378202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31378223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 79851 + ... + 80242.

Almost surely, 2^31378228 is an apocalyptic number.

It is an amenable number.

31378228 is an abundant number, since it is smaller than the sum of its proper divisors (32499278).

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

31378228 is a wasteful number, since it uses less digits than its factorization.

31378228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160111 (or 160102 counting only the distinct ones).

The product of its digits is 16128, while the sum is 34.

The square root of 31378228 is about 5601.6272635726. The cubic root of 31378228 is about 315.4104936376.

The spelling of 31378228 in words is "thirty-one million, three hundred seventy-eight thousand, two hundred twenty-eight".