331730640 has 100 divisors (see below), whose sum is σ = 1152172164. Its totient is φ = 88459776.

The previous prime is 331730621. The next prime is 331730669. The reversal of 331730640 is 46037133.

It is a happy number.

331730640 is a `hidden beast` number, since 3 + 3 + 17 + 3 + 0 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 50296464 + 281434176 = 7092^2 + 16776^2 .

It is a super-2 number, since 2×331730640² = 220090435029619200, which contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 19117 + ... + 32076.

Almost surely, 2^331730640 is an apocalyptic number.

331730640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

331730640 is an abundant number, since it is smaller than the sum of its proper divisors (820441524).

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

331730640 is a wasteful number, since it uses less digits than its factorization.

331730640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51218 (or 51203 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 27.

The square root of 331730640 is about 18213.4741331795. The cubic root of 331730640 is about 692.2482431003.

Adding to 331730640 its reverse (46037133), we get a palindrome (377767773).

The spelling of 331730640 in words is "three hundred thirty-one million, seven hundred thirty thousand, six hundred forty".