21210913260 has 192 divisors, whose sum is σ = 72909849600. Its totient is φ = 5092015104.

The previous prime is 21210913259. The next prime is 21210913313. The reversal of 21210913260 is 6231901212.

It is a Harshad number since it is a multiple of its sum of digits (27).

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 63 ways as a sum of consecutive naturals, for example, 160911 + ... + 261369.

It is an arithmetic number, because the mean of its divisors is an integer number (379738800).

Almost surely, 2^21210913260 is an apocalyptic number.

21210913260 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 21210913260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36454924800).

21210913260 is an abundant number, since it is smaller than the sum of its proper divisors (51698936340).

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

21210913260 is a wasteful number, since it uses less digits than its factorization.

21210913260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100517 (or 100509 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The spelling of 21210913260 in words is "twenty-one billion, two hundred ten million, nine hundred thirteen thousand, two hundred sixty".