21111520110 has 32 divisors (see below), whose sum is σ = 50695911072. Its totient is φ = 5626598400.

The previous prime is 21111520061. The next prime is 21111520121. The reversal of 21111520110 is 1102511112.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21111520110.

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 15 ways as a sum of consecutive naturals, for example, 141339 + ... + 249398.

It is an arithmetic number, because the mean of its divisors is an integer number (1584247221).

Almost surely, 2^21111520110 is an apocalyptic number.

21111520110 is an abundant number, since it is smaller than the sum of its proper divisors (29584390962).

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

21111520110 is a wasteful number, since it uses less digits than its factorization.

21111520110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392548.

The product of its (nonzero) digits is 20, while the sum is 15.

The spelling of 21111520110 in words is "twenty-one billion, one hundred eleven million, five hundred twenty thousand, one hundred ten".