21220221211020 has 144 divisors (see below), whose sum is σ = 69321080791872. Its totient is φ = 5223311608320.

The previous prime is 21220221210967. The next prime is 21220221211043. The reversal of 21220221211020 is 2011212202212.

It is a happy number.

21220221211020 is a `hidden beast` number, since 212 + 2 + 0 + 221 + 211 + 0 + 20 = 666.

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 = 21220221210984 and 21220221211002.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 127004254 + ... + 127171226.

It is an arithmetic number, because the mean of its divisors is an integer number (481396394388).

Almost surely, 2^{21220221211020} is an apocalyptic number.

21220221211020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21220221211020 is an abundant number, since it is smaller than the sum of its proper divisors (48100859580852).

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

21220221211020 is a wasteful number, since it uses less digits than its factorization.

21220221211020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221312 (or 221307 counting only the distinct ones).

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

Adding to 21220221211020 its reverse (2011212202212), we get a palindrome (23231433413232).

The spelling of 21220221211020 in words is "twenty-one trillion, two hundred twenty billion, two hundred twenty-one million, two hundred eleven thousand, twenty".