213138829 has 4 divisors (see below), whose sum is σ = 213203740. Its totient is φ = 213073920.

The previous prime is 213138817. The next prime is 213138839. The reversal of 213138829 is 928831312.

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 38105929 + 175032900 = 6173^2 + 13230^2 .

It is a cyclic number.

It is not a de Polignac number, because 213138829 - 2¹⁷ = 213007757 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213138839) 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, 27252 + ... + 34189.

It is an arithmetic number, because the mean of its divisors is an integer number (53300935).

Almost surely, 2^213138829 is an apocalyptic number.

It is an amenable number.

213138829 is a deficient number, since it is larger than the sum of its proper divisors (64911).

213138829 is an equidigital number, since it uses as much as digits as its factorization.

213138829 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64910.

The product of its digits is 20736, while the sum is 37.

The square root of 213138829 is about 14599.2749477500. The cubic root of 213138829 is about 597.3389833569.

The spelling of 213138829 in words is "two hundred thirteen million, one hundred thirty-eight thousand, eight hundred twenty-nine".