21313120320 has 168 divisors, whose sum is σ = 77620681944. Its totient is φ = 5349163008.

The previous prime is 21313120319. The next prime is 21313120321. The reversal of 21313120320 is 2302131312.

21313120320 is a `hidden beast` number, since 2 + 1 + 31 + 312 + 0 + 320 = 666.

It is an interprime number because it is at equal distance from previous prime (21313120319) and next prime (21313120321).

It can be written as a sum of positive squares in 4 ways, for example, as 2255870016 + 19057250304 = 47496^2 + 138048^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 21313120293 and 21313120302.

It is not an unprimeable number, because it can be changed into a prime (21313120321) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 168699 + ... + 266618.

Almost surely, 2^21313120320 is an apocalyptic number.

21313120320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21313120320 is an abundant number, since it is smaller than the sum of its proper divisors (56307561624).

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

21313120320 is a wasteful number, since it uses less digits than its factorization.

21313120320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 435357 (or 435344 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21313120320 its reverse (2302131312), we get a palindrome (23615251632).

The spelling of 21313120320 in words is "twenty-one billion, three hundred thirteen million, one hundred twenty thousand, three hundred twenty".