210345221 has 4 divisors (see below), whose sum is σ = 210554700. Its totient is φ = 210135744.

The previous prime is 210345217. The next prime is 210345229. The reversal of 210345221 is 122543012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 148108900 + 62236321 = 12170^2 + 7889^2 .

It is a cyclic number.

It is not a de Polignac number, because 210345221 - 2² = 210345217 is a prime.

It is a super-2 number, since 2×210345221² = 88490223995077682, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210345193 and 210345202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210345229) 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, 103226 + ... + 105243.

It is an arithmetic number, because the mean of its divisors is an integer number (52638675).

Almost surely, 2^210345221 is an apocalyptic number.

It is an amenable number.

210345221 is a deficient number, since it is larger than the sum of its proper divisors (209479).

210345221 is a wasteful number, since it uses less digits than its factorization.

210345221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209478.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 210345221 is about 14503.2831110752. The cubic root of 210345221 is about 594.7177259573.

Adding to 210345221 its reverse (122543012), we get a palindrome (332888233).

The spelling of 210345221 in words is "two hundred ten million, three hundred forty-five thousand, two hundred twenty-one".