213581623 has 4 divisors (see below), whose sum is σ = 214197480. Its totient is φ = 212965768.

The previous prime is 213581609. The next prime is 213581647. The reversal of 213581623 is 326185312.

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 213581623 - 2⁹ = 213581111 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 (213581653) 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, 307408 + ... + 308101.

It is an arithmetic number, because the mean of its divisors is an integer number (53549370).

Almost surely, 2^213581623 is an apocalyptic number.

213581623 is a deficient number, since it is larger than the sum of its proper divisors (615857).

213581623 is an equidigital number, since it uses as much as digits as its factorization.

213581623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 615856.

The product of its digits is 8640, while the sum is 31.

The square root of 213581623 is about 14614.4320108583. The cubic root of 213581623 is about 597.7523526868.

The spelling of 213581623 in words is "two hundred thirteen million, five hundred eighty-one thousand, six hundred twenty-three".