213132321 has 24 divisors (see below), whose sum is σ = 319359144. Its totient is φ = 136857600.

The previous prime is 213132301. The next prime is 213132331. The reversal of 213132321 is 123231312.

213132321 is a `hidden beast` number, since 213 + 132 + 321 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 117483921 + 95648400 = 10839^2 + 9780^2 .

It is not a de Polignac number, because 213132321 - 2⁷ = 213132193 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 213132294 and 213132303.

It is not an unprimeable number, because it can be changed into a prime (213132301) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30465 + ... + 36801.

It is an arithmetic number, because the mean of its divisors is an integer number (13306631).

Almost surely, 2^213132321 is an apocalyptic number.

It is an amenable number.

213132321 is a deficient number, since it is larger than the sum of its proper divisors (106226823).

213132321 is a wasteful number, since it uses less digits than its factorization.

213132321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6481 (or 6478 counting only the distinct ones).

The product of its digits is 216, while the sum is 18.

The square root of 213132321 is about 14599.0520582673. The cubic root of 213132321 is about 597.3329035611.

Adding to 213132321 its reverse (123231312), we get a palindrome (336363633).

The spelling of 213132321 in words is "two hundred thirteen million, one hundred thirty-two thousand, three hundred twenty-one".