18947149 has 8 divisors (see below), whose sum is σ = 20739992. Its totient is φ = 17202240.

The previous prime is 18947141. The next prime is 18947153. The reversal of 18947149 is 94174981.

It can be written as a sum of positive squares in 4 ways, for example, as 396900 + 18550249 = 630^2 + 4307^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18947149 - 2³ = 18947141 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18947141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11154 + ... + 12739.

It is an arithmetic number, because the mean of its divisors is an integer number (2592499).

Almost surely, 2^18947149 is an apocalyptic number.

It is an amenable number.

18947149 is a deficient number, since it is larger than the sum of its proper divisors (1792843).

18947149 is a wasteful number, since it uses less digits than its factorization.

18947149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23967.

The product of its digits is 72576, while the sum is 43.

The square root of 18947149 is about 4352.8322963330. The cubic root of 18947149 is about 266.5925180997.

The spelling of 18947149 in words is "eighteen million, nine hundred forty-seven thousand, one hundred forty-nine".