18977806 has 8 divisors (see below), whose sum is σ = 29704464. Its totient is φ = 9076320.

The previous prime is 18977773. The next prime is 18977813. The reversal of 18977806 is 60877981.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Harshad number since it is a multiple of its sum of digits (46), and also a Moran number because the ratio is a prime number: 412561 = 18977806 / (1 + 8 + 9 + 7 + 7 + 8 + 0 + 6).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 206235 + ... + 206326.

It is an arithmetic number, because the mean of its divisors is an integer number (3713058).

Almost surely, 2^18977806 is an apocalyptic number.

18977806 is a deficient number, since it is larger than the sum of its proper divisors (10726658).

18977806 is a wasteful number, since it uses less digits than its factorization.

18977806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412586.

The product of its (nonzero) digits is 169344, while the sum is 46.

The square root of 18977806 is about 4356.3523732591. The cubic root of 18977806 is about 266.7362252572.

The spelling of 18977806 in words is "eighteen million, nine hundred seventy-seven thousand, eight hundred six".