252021221 has 4 divisors (see below), whose sum is σ = 252192192. Its totient is φ = 251850252.

The previous prime is 252021199. The next prime is 252021233. The reversal of 252021221 is 122120252.

252021221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 252021221 - 2⁶ = 252021157 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 252021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (252021241) 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, 83255 + ... + 86228.

It is an arithmetic number, because the mean of its divisors is an integer number (63048048).

Almost surely, 2^252021221 is an apocalyptic number.

It is an amenable number.

252021221 is a deficient number, since it is larger than the sum of its proper divisors (170971).

252021221 is a wasteful number, since it uses less digits than its factorization.

252021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170970.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 252021221 is about 15875.1762509901. The cubic root of 252021221 is about 631.6536893562.

Adding to 252021221 its reverse (122120252), we get a palindrome (374141473).

The spelling of 252021221 in words is "two hundred fifty-two million, twenty-one thousand, two hundred twenty-one".