212323021 has 4 divisors (see below), whose sum is σ = 212366752. Its totient is φ = 212279292.

The previous prime is 212322991. The next prime is 212323031. The reversal of 212323021 is 120323212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 212323021 - 2⁷ = 212322893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212322986 and 212323004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212323031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13521 + ... + 24646.

It is an arithmetic number, because the mean of its divisors is an integer number (53091688).

Almost surely, 2^212323021 is an apocalyptic number.

It is an amenable number.

212323021 is a deficient number, since it is larger than the sum of its proper divisors (43731).

212323021 is an equidigital number, since it uses as much as digits as its factorization.

212323021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43730.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 212323021 is about 14571.3081430598. The cubic root of 212323021 is about 596.5758860601.

Adding to 212323021 its reverse (120323212), we get a palindrome (332646233).

The spelling of 212323021 in words is "two hundred twelve million, three hundred twenty-three thousand, twenty-one".