211121211220020 has 60 divisors (see below), whose sum is σ = 662295058906404. Its totient is φ = 56298989658240.

The previous prime is 211121211219911. The next prime is 211121211220093. The reversal of 211121211220020 is 20022112121112.

211121211220020 is a `hidden beast` number, since 211 + 1 + 2 + 1 + 211 + 220 + 0 + 20 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 86076125509284 + 125045085710736 = 9277722^2 + 11182356^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 211121211219975 and 211121211220002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 65160866041 + ... + 65160869280.

Almost surely, 2^{211121211220020} is an apocalyptic number.

211121211220020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211121211220020 is an abundant number, since it is smaller than the sum of its proper divisors (451173847686384).

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

211121211220020 is a wasteful number, since it uses less digits than its factorization.

211121211220020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130321735342 (or 130321735331 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 211121211220020 its reverse (20022112121112), we get a palindrome (231143323341132).

The spelling of 211121211220020 in words is "two hundred eleven trillion, one hundred twenty-one billion, two hundred eleven million, two hundred twenty thousand, twenty".