21321107260 has 96 divisors (see below), whose sum is σ = 50965770240. Its totient is φ = 7442408448.

The previous prime is 21321107251. The next prime is 21321107263. The reversal of 21321107260 is 6270112312.

It is a happy number.

It is a super-2 number, since 2×21321107260² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21321107263) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 268509 + ... + 338731.

It is an arithmetic number, because the mean of its divisors is an integer number (530893440).

Almost surely, 2^21321107260 is an apocalyptic number.

21321107260 is a gapful number since it is divisible by the number (20) 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 21321107260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25482885120).

21321107260 is an abundant number, since it is smaller than the sum of its proper divisors (29644662980).

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

21321107260 is a wasteful number, since it uses less digits than its factorization.

21321107260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70315 (or 70313 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 25.

Adding to 21321107260 its reverse (6270112312), we get a palindrome (27591219572).

The spelling of 21321107260 in words is "twenty-one billion, three hundred twenty-one million, one hundred seven thousand, two hundred sixty".