18971020 has 12 divisors (see below), whose sum is σ = 39839184. Its totient is φ = 7588400.

The previous prime is 18971009. The next prime is 18971023. The reversal of 18971020 is 2017981.

It is a self number, because there is not a number n which added to its sum of digits gives 18971020.

It is not an unprimeable number, because it can be changed into a prime (18971023) 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, 474256 + ... + 474295.

It is an arithmetic number, because the mean of its divisors is an integer number (3319932).

Almost surely, 2^18971020 is an apocalyptic number.

18971020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18971020 is an abundant number, since it is smaller than the sum of its proper divisors (20868164).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18971020 is a wasteful number, since it uses less digits than its factorization.

18971020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 948560 (or 948558 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 18971020 is about 4355.5734410064. The cubic root of 18971020 is about 266.7044286801.

The spelling of 18971020 in words is "eighteen million, nine hundred seventy-one thousand, twenty".