213209725 has 24 divisors (see below), whose sum is σ = 276712200. Its totient is φ = 162789120.

The previous prime is 213209707. The next prime is 213209753. The reversal of 213209725 is 527902312.

It can be written as a sum of positive squares in 12 ways, for example, as 50851161 + 162358564 = 7131^2 + 12742^2 .

It is not a de Polignac number, because 213209725 - 2⁵ = 213209693 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 46851 + ... + 51199.

It is an arithmetic number, because the mean of its divisors is an integer number (11529675).

Almost surely, 2^213209725 is an apocalyptic number.

213209725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

213209725 is a deficient number, since it is larger than the sum of its proper divisors (63502475).

213209725 is a wasteful number, since it uses less digits than its factorization.

213209725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4449 (or 4444 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 213209725 is about 14601.7028116586. The cubic root of 213209725 is about 597.4052066258.

The spelling of 213209725 in words is "two hundred thirteen million, two hundred nine thousand, seven hundred twenty-five".