21121272060 has 96 divisors (see below), whose sum is σ = 67839690240. Its totient is φ = 4809746688.

The previous prime is 21121272059. The next prime is 21121272077. The reversal of 21121272060 is 6027212112.

It is a super-2 number, since 2×21121272060² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21121272060.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19507 + ... + 206453.

It is an arithmetic number, because the mean of its divisors is an integer number (706663440).

Almost surely, 2^21121272060 is an apocalyptic number.

21121272060 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 21121272060, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33919845120).

21121272060 is an abundant number, since it is smaller than the sum of its proper divisors (46718418180).

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

21121272060 is a wasteful number, since it uses less digits than its factorization.

21121272060 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187235 (or 187233 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

Adding to 21121272060 its reverse (6027212112), we get a palindrome (27148484172).

The spelling of 21121272060 in words is "twenty-one billion, one hundred twenty-one million, two hundred seventy-two thousand, sixty".