18949213 has 4 divisors (see below), whose sum is σ = 19946560. Its totient is φ = 17951868.

The previous prime is 18949211. The next prime is 18949243. The reversal of 18949213 is 31294981.

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 18949213 - 2¹ = 18949211 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 (18949211) 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, 498645 + ... + 498682.

It is an arithmetic number, because the mean of its divisors is an integer number (4986640).

Almost surely, 2^18949213 is an apocalyptic number.

It is an amenable number.

18949213 is a deficient number, since it is larger than the sum of its proper divisors (997347).

18949213 is an equidigital number, since it uses as much as digits as its factorization.

18949213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 997346.

The product of its digits is 15552, while the sum is 37.

The square root of 18949213 is about 4353.0693768880. The cubic root of 18949213 is about 266.6021981308.

The spelling of 18949213 in words is "eighteen million, nine hundred forty-nine thousand, two hundred thirteen".