31328100 has 144 divisors (see below), whose sum is σ = 103535040. Its totient is φ = 8121600.

The previous prime is 31328071. The next prime is 31328113. The reversal of 31328100 is 182313.

It is a super-2 number, since 2×31328100² = 1962899699220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 110559 + ... + 110841.

Almost surely, 2^31328100 is an apocalyptic number.

31328100 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 31328100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51767520).

31328100 is an abundant number, since it is smaller than the sum of its proper divisors (72206940).

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

31328100 is a wasteful number, since it uses less digits than its factorization.

31328100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347 (or 334 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 31328100 is about 5597.1510610310. The cubic root of 31328100 is about 315.2424437377.

The spelling of 31328100 in words is "thirty-one million, three hundred twenty-eight thousand, one hundred".