18901249 has 4 divisors (see below), whose sum is σ = 18919636. Its totient is φ = 18882864.

The previous prime is 18901247. The next prime is 18901261. The reversal of 18901249 is 94210981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94210981 = 2551 ⋅36931.

It can be written as a sum of positive squares in 2 ways, for example, as 10240000 + 8661249 = 3200^2 + 2943^2 .

It is a cyclic number.

It is not a de Polignac number, because 18901249 - 2¹ = 18901247 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18901247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7554 + ... + 9739.

It is an arithmetic number, because the mean of its divisors is an integer number (4729909).

Almost surely, 2^18901249 is an apocalyptic number.

It is an amenable number.

18901249 is a deficient number, since it is larger than the sum of its proper divisors (18387).

18901249 is a wasteful number, since it uses less digits than its factorization.

18901249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18386.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 18901249 is about 4347.5566701309. The cubic root of 18901249 is about 266.3770680766.

The spelling of 18901249 in words is "eighteen million, nine hundred one thousand, two hundred forty-nine".