213665573 has 4 divisors (see below), whose sum is σ = 233089728. Its totient is φ = 194241420.

The previous prime is 213665567. The next prime is 213665579. The reversal of 213665573 is 375566312.

213665573 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (213665567) and next prime (213665579).

It is a cyclic number.

It is not a de Polignac number, because 213665573 - 2¹² = 213661477 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 (213665579) 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, 9712061 + ... + 9712082.

It is an arithmetic number, because the mean of its divisors is an integer number (58272432).

Almost surely, 2^213665573 is an apocalyptic number.

It is an amenable number.

213665573 is a deficient number, since it is larger than the sum of its proper divisors (19424155).

213665573 is a wasteful number, since it uses less digits than its factorization.

213665573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19424154.

The product of its digits is 113400, while the sum is 38.

The square root of 213665573 is about 14617.3038895687. The cubic root of 213665573 is about 597.8306595748.

The spelling of 213665573 in words is "two hundred thirteen million, six hundred sixty-five thousand, five hundred seventy-three".