212021220021 has 16 divisors (see below), whose sum is σ = 311520745536. Its totient is φ = 127440302976.

The previous prime is 212021220017. The next prime is 212021220031. The reversal of 212021220021 is 120022120212.

It is not a de Polignac number, because 212021220021 - 2² = 212021220017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212021220031) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63212760 + ... + 63216113.

It is an arithmetic number, because the mean of its divisors is an integer number (19470046596).

Almost surely, 2^212021220021 is an apocalyptic number.

It is an amenable number.

212021220021 is a deficient number, since it is larger than the sum of its proper divisors (99499525515).

212021220021 is a wasteful number, since it uses less digits than its factorization.

212021220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126428932.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 212021220021 its reverse (120022120212), we get a palindrome (332043340233).

The spelling of 212021220021 in words is "two hundred twelve billion, twenty-one million, two hundred twenty thousand, twenty-one".