18977423 has 4 divisors (see below), whose sum is σ = 20093760. Its totient is φ = 17861088.

The previous prime is 18977419. The next prime is 18977429. The reversal of 18977423 is 32477981.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18977423 - 2² = 18977419 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18977429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 558143 + ... + 558176.

It is an arithmetic number, because the mean of its divisors is an integer number (5023440).

Almost surely, 2^18977423 is an apocalyptic number.

18977423 is a deficient number, since it is larger than the sum of its proper divisors (1116337).

18977423 is a wasteful number, since it uses less digits than its factorization.

18977423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1116336.

The product of its digits is 84672, while the sum is 41.

The square root of 18977423 is about 4356.3084142425. The cubic root of 18977423 is about 266.7344308689.

The spelling of 18977423 in words is "eighteen million, nine hundred seventy-seven thousand, four hundred twenty-three".