321540032 has 56 divisors (see below), whose sum is σ = 698308992. Its totient is φ = 145683200.

The previous prime is 321540017. The next prime is 321540047. The reversal of 321540032 is 230045123.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (321540017) and next prime (321540047).

It is a super-2 number, since 2×321540032² = 206775984357122048, which contains 22 as substring.

It is a hoax number, since the sum of its digits (20) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 321539986 and 321540013.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 311357 + ... + 312387.

Almost surely, 2^321540032 is an apocalyptic number.

321540032 is a gapful number since it is divisible by the number (32) 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 321540032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (349154496).

321540032 is an abundant number, since it is smaller than the sum of its proper divisors (376768960).

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

321540032 is a wasteful number, since it uses less digits than its factorization.

321540032 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1497 (or 1487 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 321540032 is about 17931.5373574047. The cubic root of 321540032 is about 685.0858805071.

Adding to 321540032 its reverse (230045123), we get a palindrome (551585155).

The spelling of 321540032 in words is "three hundred twenty-one million, five hundred forty thousand, thirty-two".