18401380 has 48 divisors (see below), whose sum is σ = 40803840. Its totient is φ = 6956928.

The previous prime is 18401371. The next prime is 18401381. The reversal of 18401380 is 8310481.

It is a super-2 number, since 2×18401380² = 677221571808800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18401381) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49957 + ... + 50323.

It is an arithmetic number, because the mean of its divisors is an integer number (850080).

Almost surely, 2^18401380 is an apocalyptic number.

18401380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18401380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20401920).

18401380 is an abundant number, since it is smaller than the sum of its proper divisors (22402460).

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

18401380 is a wasteful number, since it uses less digits than its factorization.

18401380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 508 (or 506 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 18401380 is about 4289.6829719689. The cubic root of 18401380 is about 264.0078242248.

It can be divided in two parts, 18401 and 380, that added together give a palindrome (18781).

The spelling of 18401380 in words is "eighteen million, four hundred one thousand, three hundred eighty".