21320321130 has 96 divisors (see below), whose sum is σ = 57114467280. Its totient is φ = 5515361280.

The previous prime is 21320321119. The next prime is 21320321159. The reversal of 21320321130 is 3112302312.

21320321130 is a `hidden beast` number, since 21 + 320 + 321 + 1 + 3 + 0 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 4268923569 + 17051397561 = 65337^2 + 130581^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 399420 + ... + 449640.

Almost surely, 2^21320321130 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21320321130, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28557233640).

21320321130 is an abundant number, since it is smaller than the sum of its proper divisors (35794146150).

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

21320321130 is a wasteful number, since it uses less digits than its factorization.

21320321130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50376 (or 50373 counting only the distinct ones).

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

Adding to 21320321130 its reverse (3112302312), we get a palindrome (24432623442).

The spelling of 21320321130 in words is "twenty-one billion, three hundred twenty million, three hundred twenty-one thousand, one hundred thirty".