21111323120 has 40 divisors (see below), whose sum is σ = 50281000560. Its totient is φ = 8238563840.

The previous prime is 21111323071. The next prime is 21111323131. The reversal of 21111323120 is 2132311112.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3214910 + ... + 3221469.

It is an arithmetic number, because the mean of its divisors is an integer number (1257025014).

Almost surely, 2^21111323120 is an apocalyptic number.

21111323120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21111323120 is an abundant number, since it is smaller than the sum of its proper divisors (29169677440).

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

21111323120 is a wasteful number, since it uses less digits than its factorization.

21111323120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6436433 (or 6436427 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21111323120 its reverse (2132311112), we get a palindrome (23243634232).

It can be divided in two parts, 2111 and 1323120, that added together give a palindrome (1325231).

The spelling of 21111323120 in words is "twenty-one billion, one hundred eleven million, three hundred twenty-three thousand, one hundred twenty".