321638999040 has 1232 divisors, whose sum is σ = 1267139540592. Its totient is φ = 77970014208.

The previous prime is 321638999021. The next prime is 321638999041. The reversal of 321638999040 is 40999836123.

321638999040 is a `hidden beast` number, since 3 + 216 + 389 + 9 + 9 + 0 + 40 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 37456183296 + 284182815744 = 193536^2 + 533088^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (321638999041) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 2347729852 + ... + 2347729988.

Almost surely, 2^321638999040 is an apocalyptic number.

321638999040 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 321638999040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (633569770296).

321638999040 is an abundant number, since it is smaller than the sum of its proper divisors (945500541552).

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

321638999040 is a wasteful number, since it uses less digits than its factorization.

321638999040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234 (or 201 counting only the distinct ones).

The product of its (nonzero) digits is 2519424, while the sum is 54.

The spelling of 321638999040 in words is "three hundred twenty-one billion, six hundred thirty-eight million, nine hundred ninety-nine thousand, forty".