18401438 has 12 divisors (see below), whose sum is σ = 30339960. Its totient is φ = 8364180.

The previous prime is 18401437. The next prime is 18401459. The reversal of 18401438 is 83410481.

It is a super-2 number, since 2×18401438² = 677225840935688, which contains 22 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 18401438.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18401431) 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 5 ways as a sum of consecutive naturals, for example, 37778 + ... + 38261.

It is an arithmetic number, because the mean of its divisors is an integer number (2528330).

Almost surely, 2^18401438 is an apocalyptic number.

18401438 is a deficient number, since it is larger than the sum of its proper divisors (11938522).

18401438 is a wasteful number, since it uses less digits than its factorization.

18401438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76063 (or 76052 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 18401438 is about 4289.6897323699. The cubic root of 18401438 is about 264.0081016032.

The spelling of 18401438 in words is "eighteen million, four hundred one thousand, four hundred thirty-eight".