21021111121110 has 16 divisors (see below), whose sum is σ = 50450666690736. Its totient is φ = 5605629632288.

The previous prime is 21021111121097. The next prime is 21021111121123. The reversal of 21021111121110 is 1112111112012.

It is an interprime number because it is at equal distance from previous prime (21021111121097) and next prime (21021111121123).

It is a super-2 number, since 2×21021111121110² (a number of 27 digits) contains 22 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21021111121110.

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, 350351851989 + ... + 350351852048.

It is an arithmetic number, because the mean of its divisors is an integer number (3153166668171).

Almost surely, 2^{21021111121110} is an apocalyptic number.

21021111121110 is an abundant number, since it is smaller than the sum of its proper divisors (29429555569626).

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

21021111121110 is a wasteful number, since it uses less digits than its factorization.

21021111121110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 700703704047.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 21021111121110 its reverse (1112111112012), we get a palindrome (22133222233122).

The spelling of 21021111121110 in words is "twenty-one trillion, twenty-one billion, one hundred eleven million, one hundred twenty-one thousand, one hundred ten".