213604261 has 4 divisors (see below), whose sum is σ = 230035372. Its totient is φ = 197173152.

The previous prime is 213604231. The next prime is 213604273. The reversal of 213604261 is 162406312.

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 107122500 + 106481761 = 10350^2 + 10319^2 .

It is a cyclic number.

It is not a de Polignac number, because 213604261 - 2⁹ = 213603749 is a prime.

It is a super-2 number, since 2×213604261² = 91253560634712242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213604231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8215536 + ... + 8215561.

It is an arithmetic number, because the mean of its divisors is an integer number (57508843).

Almost surely, 2^213604261 is an apocalyptic number.

It is an amenable number.

213604261 is a deficient number, since it is larger than the sum of its proper divisors (16431111).

213604261 is a wasteful number, since it uses less digits than its factorization.

213604261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16431110.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 213604261 is about 14615.2064987122. The cubic root of 213604261 is about 597.7734709826.

The spelling of 213604261 in words is "two hundred thirteen million, six hundred four thousand, two hundred sixty-one".