1155921 has 16 divisors (see below), whose sum is σ = 1681344. Its totient is φ = 702144.

The previous prime is 1155919. The next prime is 1155923. The reversal of 1155921 is 1295511.

It is an interprime number because it is at equal distance from previous prime (1155919) and next prime (1155923).

It is not a de Polignac number, because 1155921 - 2¹ = 1155919 is a prime.

It is an Ulam number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1155891 and 1155900.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1155923) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4035 + ... + 4311.

It is an arithmetic number, because the mean of its divisors is an integer number (105084).

2^1155921 is an apocalyptic number.

It is an amenable number.

1155921 is a deficient number, since it is larger than the sum of its proper divisors (525423).

1155921 is a wasteful number, since it uses less digits than its factorization.

1155921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400.

The product of its digits is 450, while the sum is 24.

The square root of 1155921 is about 1075.1376656038. The cubic root of 1155921 is about 104.9484554265.

The spelling of 1155921 in words is "one million, one hundred fifty-five thousand, nine hundred twenty-one".