21011110001020 has 48 divisors (see below), whose sum is σ = 45151400448000. Its totient is φ = 8208638093376.

The previous prime is 21011110001003. The next prime is 21011110001059. The reversal of 21011110001020 is 2010001111012.

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

It is a junction number, because it is equal to n+sod(n) for n = 21011110000988 and 21011110001006.

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, 19904481 + ... + 20933479.

It is an arithmetic number, because the mean of its divisors is an integer number (940654176000).

Almost surely, 2^{21011110001020} is an apocalyptic number.

21011110001020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21011110001020 is an abundant number, since it is smaller than the sum of its proper divisors (24140290446980).

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

21011110001020 is a wasteful number, since it uses less digits than its factorization.

21011110001020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1052794 (or 1052792 counting only the distinct ones).

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

Adding to 21011110001020 its reverse (2010001111012), we get a palindrome (23021111112032).

The spelling of 21011110001020 in words is "twenty-one trillion, eleven billion, one hundred ten million, one thousand, twenty".