18806971 has 4 divisors (see below), whose sum is σ = 19115344. Its totient is φ = 18498600.

The previous prime is 18806951. The next prime is 18807001. The reversal of 18806971 is 17960881.

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 18806971 - 2¹⁹ = 18282683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18806951) 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, 154095 + ... + 154216.

It is an arithmetic number, because the mean of its divisors is an integer number (4778836).

Almost surely, 2^18806971 is an apocalyptic number.

18806971 is a deficient number, since it is larger than the sum of its proper divisors (308373).

18806971 is an equidigital number, since it uses as much as digits as its factorization.

18806971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308372.

The product of its (nonzero) digits is 24192, while the sum is 40.

The square root of 18806971 is about 4336.7004738626. The cubic root of 18806971 is about 265.9334401086.

The spelling of 18806971 in words is "eighteen million, eight hundred six thousand, nine hundred seventy-one".