31728480 has 288 divisors, whose sum is σ = 124104960. Its totient is φ = 6773760.

The previous prime is 31728467. The next prime is 31728491. The reversal of 31728480 is 8482713.

It is a super-2 number, since 2×31728480² = 2013392886220800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 446845 + ... + 446915.

It is an arithmetic number, because the mean of its divisors is an integer number (430920).

Almost surely, 2^31728480 is an apocalyptic number.

31728480 is a gapful number since it is divisible by the number (30) 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 31728480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62052480).

31728480 is an abundant number, since it is smaller than the sum of its proper divisors (92376480).

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

31728480 is a wasteful number, since it uses less digits than its factorization.

31728480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 31728480 is about 5632.8039198964. The cubic root of 31728480 is about 316.5797188188.

The spelling of 31728480 in words is "thirty-one million, seven hundred twenty-eight thousand, four hundred eighty".