21001121110 has 16 divisors (see below), whose sum is σ = 39105536400. Its totient is φ = 8110777696.

The previous prime is 21001121087. The next prime is 21001121131. The reversal of 21001121110 is 1112110012.

It is a Harshad number since it is a multiple of its sum of digits (10).

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 7 ways as a sum of consecutive naturals, for example, 36208540 + ... + 36209119.

It is an arithmetic number, because the mean of its divisors is an integer number (2444096025).

Almost surely, 2^21001121110 is an apocalyptic number.

21001121110 is a deficient number, since it is larger than the sum of its proper divisors (18104415290).

21001121110 is a wasteful number, since it uses less digits than its factorization.

21001121110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72417695.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21001121110 its reverse (1112110012), we get a palindrome (22113231122).

The spelling of 21001121110 in words is "twenty-one billion, one million, one hundred twenty-one thousand, one hundred ten".