31486720 has 72 divisors (see below), whose sum is σ = 79912224. Its totient is φ = 11845632.

The previous prime is 31486711. The next prime is 31486723. The reversal of 31486720 is 2768413.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (31486723) 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, 21037 + ... + 22483.

It is an arithmetic number, because the mean of its divisors is an integer number (1109892).

Almost surely, 2^31486720 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 31486720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39956112).

31486720 is an abundant number, since it is smaller than the sum of its proper divisors (48425504).

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

31486720 is a wasteful number, since it uses less digits than its factorization.

31486720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1485 (or 1471 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 31486720 is about 5611.3028790113. The cubic root of 31486720 is about 315.7735920278.

The spelling of 31486720 in words is "thirty-one million, four hundred eighty-six thousand, seven hundred twenty".