18805649 has 8 divisors (see below), whose sum is σ = 19850880. Its totient is φ = 17766000.

The previous prime is 18805643. The next prime is 18805667. The reversal of 18805649 is 94650881.

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 18805649 - 2¹² = 18801553 is a prime.

It is a super-2 number, since 2×18805649² = 707304868622402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18805643) 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, 6824 + ... + 9174.

It is an arithmetic number, because the mean of its divisors is an integer number (2481360).

Almost surely, 2^18805649 is an apocalyptic number.

18805649 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

18805649 is a deficient number, since it is larger than the sum of its proper divisors (1045231).

18805649 is a wasteful number, since it uses less digits than its factorization.

18805649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2791.

The product of its (nonzero) digits is 69120, while the sum is 41.

The square root of 18805649 is about 4336.5480511577. The cubic root of 18805649 is about 265.9272088687.

The spelling of 18805649 in words is "eighteen million, eight hundred five thousand, six hundred forty-nine".