218947433 has 4 divisors (see below), whose sum is σ = 220397568. Its totient is φ = 217497300.

The previous prime is 218947427. The next prime is 218947441. The reversal of 218947433 is 334749812.

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 a cyclic number.

It is not a de Polignac number, because 218947433 - 2⁸ = 218947177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (218947453) 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, 724841 + ... + 725142.

It is an arithmetic number, because the mean of its divisors is an integer number (55099392).

Almost surely, 2^218947433 is an apocalyptic number.

It is an amenable number.

218947433 is a deficient number, since it is larger than the sum of its proper divisors (1450135).

218947433 is a wasteful number, since it uses less digits than its factorization.

218947433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1450134.

The product of its digits is 145152, while the sum is 41.

The square root of 218947433 is about 14796.8724060188. The cubic root of 218947433 is about 602.7167845323.

The spelling of 218947433 in words is "two hundred eighteen million, nine hundred forty-seven thousand, four hundred thirty-three".