213506123 has 4 divisors (see below), whose sum is σ = 214939200. Its totient is φ = 212073048.

The previous prime is 213506119. The next prime is 213506131. The reversal of 213506123 is 321605312.

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

It is a cyclic number.

It is not a de Polignac number, because 213506123 - 2² = 213506119 is a prime.

It is a super-2 number, since 2×213506123² = 91169729116982258, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213506113) 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, 716315 + ... + 716612.

It is an arithmetic number, because the mean of its divisors is an integer number (53734800).

Almost surely, 2^213506123 is an apocalyptic number.

213506123 is a deficient number, since it is larger than the sum of its proper divisors (1433077).

213506123 is a wasteful number, since it uses less digits than its factorization.

213506123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1433076.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 213506123 is about 14611.8487194468. The cubic root of 213506123 is about 597.6819102632.

The spelling of 213506123 in words is "two hundred thirteen million, five hundred six thousand, one hundred twenty-three".