18157440 has 192 divisors, whose sum is σ = 67674960. Its totient is φ = 4128768.

The previous prime is 18157421. The next prime is 18157441. The reversal of 18157440 is 4475181.

It is a tau number, because it is divible by the number of its divisors (192).

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 18157398 and 18157407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18157441) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 93984 + ... + 94176.

Almost surely, 2^18157440 is an apocalyptic number.

18157440 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 18157440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33837480).

18157440 is an abundant number, since it is smaller than the sum of its proper divisors (49517520).

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

18157440 is a wasteful number, since it uses less digits than its factorization.

18157440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229 (or 210 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 30.

The square root of 18157440 is about 4261.1547730633. The cubic root of 18157440 is about 262.8360141447.

The spelling of 18157440 in words is "eighteen million, one hundred fifty-seven thousand, four hundred forty".