31390128 has 240 divisors, whose sum is σ = 116064000. Its totient is φ = 7672320.

The previous prime is 31390127. The next prime is 31390141. The reversal of 31390128 is 82109313.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31390127) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 210598 + ... + 210746.

It is an arithmetic number, because the mean of its divisors is an integer number (483600).

Almost surely, 2^31390128 is an apocalyptic number.

31390128 is a gapful number since it is divisible by the number (38) 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 31390128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (58032000).

31390128 is an abundant number, since it is smaller than the sum of its proper divisors (84673872).

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

31390128 is a wasteful number, since it uses less digits than its factorization.

31390128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200 (or 191 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 31390128 is about 5602.6893542298. The cubic root of 31390128 is about 315.4503610949.

The spelling of 31390128 in words is "thirty-one million, three hundred ninety thousand, one hundred twenty-eight".