18212961 has 12 divisors (see below), whose sum is σ = 26296368. Its totient is φ = 11207664.

The previous prime is 18212947. The next prime is 18212969. The reversal of 18212961 is 16921281.

It is a happy number.

It is not a de Polignac number, because 18212961 - 2⁷ = 18212833 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18212969) 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 11 ways as a sum of consecutive naturals, for example, 17455 + ... + 18468.

It is an arithmetic number, because the mean of its divisors is an integer number (2191364).

Almost surely, 2^18212961 is an apocalyptic number.

It is an amenable number.

18212961 is a deficient number, since it is larger than the sum of its proper divisors (8083407).

18212961 is a wasteful number, since it uses less digits than its factorization.

18212961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35952 (or 35939 counting only the distinct ones).

The product of its digits is 1728, while the sum is 30.

The square root of 18212961 is about 4267.6645838210. The cubic root of 18212961 is about 263.1036375854.

The spelling of 18212961 in words is "eighteen million, two hundred twelve thousand, nine hundred sixty-one".