1815315156 has 18 divisors (see below), whose sum is σ = 4588713402. Its totient is φ = 605105040.

The previous prime is 1815315113. The next prime is 1815315191. The reversal of 1815315156 is 6515135181.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1055210256 + 760104900 = 32484^2 + 27570^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-3 number, since 3×1815315156³ (a number of 29 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 50425421 = 1815315156 / (1 + 8 + 1 + 5 + 3 + 1 + 5 + 1 + 5 + 6).

It is a self number, because there is not a number n which added to its sum of digits gives 1815315156.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 25212675 + ... + 25212746.

Almost surely, 2^1815315156 is an apocalyptic number.

It is an amenable number.

1815315156 is an abundant number, since it is smaller than the sum of its proper divisors (2773398246).

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

1815315156 is a wasteful number, since it uses less digits than its factorization.

1815315156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50425431 (or 50425426 counting only the distinct ones).

The product of its digits is 18000, while the sum is 36.

The square root of 1815315156 is about 42606.5154172458. The cubic root of 1815315156 is about 1219.8806557091.

The spelling of 1815315156 in words is "one billion, eight hundred fifteen million, three hundred fifteen thousand, one hundred fifty-six".