1815120 has 60 divisors (see below), whose sum is σ = 6098196. Its totient is φ = 483840.

The previous prime is 1815103. The next prime is 1815131. The reversal of 1815120 is 215181.

It can be written as a sum of positive squares in 2 ways, for example, as 197136 + 1617984 = 444^2 + 1272^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a super-2 number, since 2×1815120² = 6589321228800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1815093 and 1815102.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 541 + ... + 1980.

2^1815120 is an apocalyptic number.

1815120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1815120 is an abundant number, since it is smaller than the sum of its proper divisors (4283076).

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

1815120 is a wasteful number, since it uses less digits than its factorization.

1815120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2540 (or 2531 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 18.

The square root of 1815120 is about 1347.2638939718. The cubic root of 1815120 is about 121.9836939597.

The spelling of 1815120 in words is "one million, eight hundred fifteen thousand, one hundred twenty".