18443977 has 8 divisors (see below), whose sum is σ = 19130112. Its totient is φ = 17763600.

The previous prime is 18443969. The next prime is 18443987. The reversal of 18443977 is 77934481.

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 18443977 - 2³ = 18443969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18443987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5727 + ... + 8347.

It is an arithmetic number, because the mean of its divisors is an integer number (2391264).

Almost surely, 2^18443977 is an apocalyptic number.

It is an amenable number.

18443977 is a deficient number, since it is larger than the sum of its proper divisors (686135).

18443977 is a wasteful number, since it uses less digits than its factorization.

18443977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2879.

The product of its digits is 169344, while the sum is 43.

The square root of 18443977 is about 4294.6451541425. The cubic root of 18443977 is about 264.2113827760.

The spelling of 18443977 in words is "eighteen million, four hundred forty-three thousand, nine hundred seventy-seven".