18151940 has 24 divisors (see below), whose sum is σ = 38767680. Its totient is φ = 7137248.

The previous prime is 18151933. The next prime is 18151949. The reversal of 18151940 is 4915181.

It is not an unprimeable number, because it can be changed into a prime (18151949) 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, 6512 + ... + 8871.

It is an arithmetic number, because the mean of its divisors is an integer number (1615320).

Almost surely, 2^18151940 is an apocalyptic number.

18151940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18151940 is an abundant number, since it is smaller than the sum of its proper divisors (20615740).

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

18151940 is a wasteful number, since it uses less digits than its factorization.

18151940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15451 (or 15449 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 29.

The square root of 18151940 is about 4260.5093592199. The cubic root of 18151940 is about 262.8094732509.

It can be divided in two parts, 18151 and 940, that added together give a palindrome (19091).

The spelling of 18151940 in words is "eighteen million, one hundred fifty-one thousand, nine hundred forty".