212221320421 has 32 divisors (see below), whose sum is σ = 242663827968. Its totient is φ = 183905379840.

The previous prime is 212221320403. The next prime is 212221320461. The reversal of 212221320421 is 124023122212.

It is a cyclic number.

It is not a de Polignac number, because 212221320421 - 2⁷ = 212221320293 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212221320392 and 212221320401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212221320461) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3725671 + ... + 3782203.

It is an arithmetic number, because the mean of its divisors is an integer number (7583244624).

Almost surely, 2^212221320421 is an apocalyptic number.

It is an amenable number.

212221320421 is a deficient number, since it is larger than the sum of its proper divisors (30442507547).

212221320421 is a wasteful number, since it uses less digits than its factorization.

212221320421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56781.

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 212221320421 its reverse (124023122212), we get a palindrome (336244442633).

The spelling of 212221320421 in words is "two hundred twelve billion, two hundred twenty-one million, three hundred twenty thousand, four hundred twenty-one".