18919071 has 12 divisors (see below), whose sum is σ = 27379872. Its totient is φ = 12588576.

The previous prime is 18919067. The next prime is 18919091. The reversal of 18919071 is 17091981.

It is not a de Polignac number, because 18919071 - 2² = 18919067 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18919091) 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 11 ways as a sum of consecutive naturals, for example, 3850 + ... + 7256.

It is an arithmetic number, because the mean of its divisors is an integer number (2281656).

Almost surely, 2^18919071 is an apocalyptic number.

18919071 is a deficient number, since it is larger than the sum of its proper divisors (8460801).

18919071 is a wasteful number, since it uses less digits than its factorization.

18919071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4030 (or 4027 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 36.

The square root of 18919071 is about 4349.6058442116. The cubic root of 18919071 is about 266.4607641468.

The spelling of 18919071 in words is "eighteen million, nine hundred nineteen thousand, seventy-one".