1121815 has 4 divisors (see below), whose sum is σ = 1346184. Its totient is φ = 897448.

The previous prime is 1121737. The next prime is 1121819. The reversal of 1121815 is 5181211.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1121815 - 2¹⁵ = 1089047 is a prime.

It is an Ulam number.

It is a Duffinian number.

1121815 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 1121792 and 1121801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1121819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112177 + ... + 112186.

It is an arithmetic number, because the mean of its divisors is an integer number (336546).

2^1121815 is an apocalyptic number.

1121815 is a deficient number, since it is larger than the sum of its proper divisors (224369).

1121815 is an equidigital number, since it uses as much as digits as its factorization.

1121815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224368.

The product of its digits is 80, while the sum is 19.

The square root of 1121815 is about 1059.1576842000. The cubic root of 1121815 is about 103.9059492425.

It can be divided in two parts, 1121 and 815, that added together give a square (1936 = 44²).

The spelling of 1121815 in words is "one million, one hundred twenty-one thousand, eight hundred fifteen".