18212940 has 36 divisors (see below), whose sum is σ = 55246464. Its totient is φ = 4856736.

The previous prime is 18212893. The next prime is 18212947. The reversal of 18212940 is 4921281.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×18212940² = 663422366887200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18212947) 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, 50412 + ... + 50771.

It is an arithmetic number, because the mean of its divisors is an integer number (1534624).

Almost surely, 2^18212940 is an apocalyptic number.

18212940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18212940 is an abundant number, since it is smaller than the sum of its proper divisors (37033524).

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

18212940 is a wasteful number, since it uses less digits than its factorization.

18212940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101198 (or 101193 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 18212940 is about 4267.6621234582. The cubic root of 18212940 is about 263.1035364637.

It can be divided in two parts, 1821 and 2940, that added together give a square (4761 = 69²).

The spelling of 18212940 in words is "eighteen million, two hundred twelve thousand, nine hundred forty".