210031221 has 8 divisors (see below), whose sum is σ = 286554400. Its totient is φ = 136764432.

The previous prime is 210031207. The next prime is 210031247. The reversal of 210031221 is 122130012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 210031221 - 2²³ = 201642613 is a prime.

It is a super-2 number, since 2×210031221² = 88226227589501682, 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 = 210031197 and 210031206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210031201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 813946 + ... + 814203.

It is an arithmetic number, because the mean of its divisors is an integer number (35819300).

Almost surely, 2^210031221 is an apocalyptic number.

It is an amenable number.

210031221 is a deficient number, since it is larger than the sum of its proper divisors (76523179).

210031221 is a wasteful number, since it uses less digits than its factorization.

210031221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1628195.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 210031221 is about 14492.4539329956. The cubic root of 210031221 is about 594.4216501956.

Adding to 210031221 its reverse (122130012), we get a palindrome (332161233).

The spelling of 210031221 in words is "two hundred ten million, thirty-one thousand, two hundred twenty-one".