21110221021020 has 48 divisors (see below), whose sum is σ = 59111925683328. Its totient is φ = 5629077336640.

The previous prime is 21110221021003. The next prime is 21110221021037. The reversal of 21110221021020 is 2012012201112.

It is an interprime number because it is at equal distance from previous prime (21110221021003) and next prime (21110221021037).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8759334 + ... + 10906253.

It is an arithmetic number, because the mean of its divisors is an integer number (1231498451736).

Almost surely, 2^{21110221021020} is an apocalyptic number.

21110221021020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21110221021020 is an abundant number, since it is smaller than the sum of its proper divisors (38001704662308).

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

21110221021020 is a wasteful number, since it uses less digits than its factorization.

21110221021020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19683490 (or 19683488 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21110221021020 its reverse (2012012201112), we get a palindrome (23122233222132).

The spelling of 21110221021020 in words is "twenty-one trillion, one hundred ten billion, two hundred twenty-one million, twenty-one thousand, twenty".