218807949 has 4 divisors (see below), whose sum is σ = 291743936. Its totient is φ = 145871964.

The previous prime is 218807923. The next prime is 218807957. The reversal of 218807949 is 949708812.

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 not a de Polignac number, because 218807949 - 2¹⁷ = 218676877 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 218807898 and 218807907.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218807999) 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, 36467989 + ... + 36467994.

It is an arithmetic number, because the mean of its divisors is an integer number (72935984).

Almost surely, 2^218807949 is an apocalyptic number.

It is an amenable number.

218807949 is a deficient number, since it is larger than the sum of its proper divisors (72935987).

218807949 is an equidigital number, since it uses as much as digits as its factorization.

218807949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72935986.

The product of its (nonzero) digits is 290304, while the sum is 48.

The square root of 218807949 is about 14792.1583617807. The cubic root of 218807949 is about 602.5887671878.

The spelling of 218807949 in words is "two hundred eighteen million, eight hundred seven thousand, nine hundred forty-nine".