2101821192820 has 48 divisors (see below), whose sum is σ = 4458699737856. Its totient is φ = 832185200000.

The previous prime is 2101821192799. The next prime is 2101821192827. The reversal of 2101821192820 is 282911281012.

It is a self number, because there is not a number n which added to its sum of digits gives 2101821192820.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2101821192827) 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 15 ways as a sum of consecutive naturals, for example, 7643925 + ... + 7914115.

It is an arithmetic number, because the mean of its divisors is an integer number (92889577872).

Almost surely, 2^{2101821192820} is an apocalyptic number.

2101821192820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2101821192820 is an abundant number, since it is smaller than the sum of its proper divisors (2356878545036).

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

2101821192820 is a wasteful number, since it uses less digits than its factorization.

2101821192820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274152 (or 274150 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 37.

The spelling of 2101821192820 in words is "two trillion, one hundred one billion, eight hundred twenty-one million, one hundred ninety-two thousand, eight hundred twenty".