213221031 has 8 divisors (see below), whose sum is σ = 284454144. Its totient is φ = 142067640.

The previous prime is 213221011. The next prime is 213221053. The reversal of 213221031 is 130122312.

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

It is not a de Polignac number, because 213221031 - 2⁹ = 213220519 is a prime.

It is a super-2 number, since 2×213221031² = 90926416121405922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 213221031.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213221011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13381 + ... + 24606.

It is an arithmetic number, because the mean of its divisors is an integer number (35556768).

Almost surely, 2^213221031 is an apocalyptic number.

213221031 is a deficient number, since it is larger than the sum of its proper divisors (71233113).

213221031 is a wasteful number, since it uses less digits than its factorization.

213221031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39861.

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 213221031 is about 14602.0899531540. The cubic root of 213221031 is about 597.4157660939.

Adding to 213221031 its reverse (130122312), we get a palindrome (343343343).

The spelling of 213221031 in words is "two hundred thirteen million, two hundred twenty-one thousand, thirty-one".