221212210221020 has 48 divisors (see below), whose sum is σ = 485462837680128. Its totient is φ = 84588221686080.

The previous prime is 221212210220927. The next prime is 221212210221031. The reversal of 221212210221020 is 20122012212122.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 221212210220983 and 221212210221001.

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, 2736379796 + ... + 2736460635.

It is an arithmetic number, because the mean of its divisors is an integer number (10113809118336).

Almost surely, 2^{221212210221020} is an apocalyptic number.

221212210221020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221212210221020 is an abundant number, since it is smaller than the sum of its proper divisors (264250627459108).

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

221212210221020 is a wasteful number, since it uses less digits than its factorization.

221212210221020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5472840530 (or 5472840528 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 221212210221020 its reverse (20122012212122), we get a palindrome (241334222433142).

The spelling of 221212210221020 in words is "two hundred twenty-one trillion, two hundred twelve billion, two hundred ten million, two hundred twenty-one thousand, twenty".