31408128 has 120 divisors (see below), whose sum is σ = 94368960. Its totient is φ = 10321920.

The previous prime is 31408127. The next prime is 31408141. The reversal of 31408128 is 82180413.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31408123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 442333 + ... + 442403.

It is an arithmetic number, because the mean of its divisors is an integer number (786408).

Almost surely, 2^31408128 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 31408128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47184480).

31408128 is an abundant number, since it is smaller than the sum of its proper divisors (62960832).

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

31408128 is an frugal number, since it uses more digits than its factorization.

31408128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 31408128 is about 5604.2954954213. The cubic root of 31408128 is about 315.5106456692.

The spelling of 31408128 in words is "thirty-one million, four hundred eight thousand, one hundred twenty-eight".