18906407 has 4 divisors (see below), whose sum is σ = 20360760. Its totient is φ = 17452056.

The previous prime is 18906383. The next prime is 18906409. The reversal of 18906407 is 70460981.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18906407 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 (18906409) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 727157 + ... + 727182.

It is an arithmetic number, because the mean of its divisors is an integer number (5090190).

Almost surely, 2^18906407 is an apocalyptic number.

18906407 is a deficient number, since it is larger than the sum of its proper divisors (1454353).

18906407 is a wasteful number, since it uses less digits than its factorization.

18906407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1454352.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 18906407 is about 4348.1498364247. The cubic root of 18906407 is about 266.4012965981.

The spelling of 18906407 in words is "eighteen million, nine hundred six thousand, four hundred seven".