321606540 has 144 divisors (see below), whose sum is σ = 1033643520. Its totient is φ = 80714880.

The previous prime is 321606449. The next prime is 321606569. The reversal of 321606540 is 45606123.

321606540 is a `hidden beast` number, since 3 + 2 + 1 + 6 + 0 + 654 + 0 = 666.

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, 926647 + ... + 926993.

It is an arithmetic number, because the mean of its divisors is an integer number (7178080).

Almost surely, 2^321606540 is an apocalyptic number.

321606540 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 321606540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (516821760).

321606540 is an abundant number, since it is smaller than the sum of its proper divisors (712036980).

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

321606540 is a wasteful number, since it uses less digits than its factorization.

321606540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 652 (or 647 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 321606540 is about 17933.3917595083. The cubic root of 321606540 is about 685.1331121072.

The spelling of 321606540 in words is "three hundred twenty-one million, six hundred six thousand, five hundred forty".