1820200200021 has 32 divisors (see below), whose sum is σ = 3081904753920. Its totient is φ = 1040085945792.

The previous prime is 1820200199999. The next prime is 1820200200067. The reversal of 1820200200021 is 1200020020281.

It is a happy number.

It is not a de Polignac number, because 1820200200021 - 2⁷ = 1820200199893 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1820200199967 and 1820200200003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1820200200121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8178411 + ... + 8398023.

It is an arithmetic number, because the mean of its divisors is an integer number (96309523560).

Almost surely, 2^{1820200200021} is an apocalyptic number.

It is an amenable number.

1820200200021 is a deficient number, since it is larger than the sum of its proper divisors (1261704553899).

1820200200021 is a wasteful number, since it uses less digits than its factorization.

1820200200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263482 (or 263476 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The spelling of 1820200200021 in words is "one trillion, eight hundred twenty billion, two hundred million, two hundred thousand, twenty-one".