1815145 has 8 divisors (see below), whose sum is σ = 2208456. Its totient is φ = 1431936.

The previous prime is 1815131. The next prime is 1815179. The reversal of 1815145 is 5415181.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 316969 + 1498176 = 563^2 + 1224^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1815145 - 2¹³ = 1806953 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2122 + ... + 2851.

It is an arithmetic number, because the mean of its divisors is an integer number (276057).

2^1815145 is an apocalyptic number.

It is an amenable number.

1815145 is a deficient number, since it is larger than the sum of its proper divisors (393311).

1815145 is an equidigital number, since it uses as much as digits as its factorization.

1815145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5051.

The product of its digits is 800, while the sum is 25.

The square root of 1815145 is about 1347.2731720034. The cubic root of 1815145 is about 121.9842539922.

It can be divided in two parts, 1815 and 145, that multiplied together give a triangular number (263175 = T₇₂₅).

The spelling of 1815145 in words is "one million, eight hundred fifteen thousand, one hundred forty-five".