18949428 has 18 divisors (see below), whose sum is σ = 47900034. Its totient is φ = 6316464.

The previous prime is 18949423. The next prime is 18949457. The reversal of 18949428 is 82494981.

18949428 is a `hidden beast` number, since 189 + 49 + 428 = 666.

It can be written as a sum of positive squares in only one way, i.e., 12659364 + 6290064 = 3558^2 + 2508^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18949423) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 263151 + ... + 263222.

It is an arithmetic number, because the mean of its divisors is an integer number (2661113).

Almost surely, 2^18949428 is an apocalyptic number.

18949428 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

18949428 is an abundant number, since it is smaller than the sum of its proper divisors (28950606).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18949428 is a wasteful number, since it uses less digits than its factorization.

18949428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 526383 (or 526378 counting only the distinct ones).

The product of its digits is 165888, while the sum is 45.

The square root of 18949428 is about 4353.0940720366. The cubic root of 18949428 is about 266.6032064270.

The spelling of 18949428 in words is "eighteen million, nine hundred forty-nine thousand, four hundred twenty-eight".