18426440 has 32 divisors (see below), whose sum is σ = 41879160. Its totient is φ = 7296000.

The previous prime is 18426437. The next prime is 18426449. The reversal of 18426440 is 4462481.

It can be written as a sum of positive squares in 4 ways, for example, as 17255716 + 1170724 = 4154^2 + 1082^2 .

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18426449) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1760 + ... + 6320.

Almost surely, 2^18426440 is an apocalyptic number.

18426440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18426440 is an abundant number, since it is smaller than the sum of its proper divisors (23452720).

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

18426440 is a wasteful number, since it uses less digits than its factorization.

18426440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4673 (or 4669 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 29.

The square root of 18426440 is about 4292.6029399422. The cubic root of 18426440 is about 264.1276165988.

The spelling of 18426440 in words is "eighteen million, four hundred twenty-six thousand, four hundred forty".