1231155 has 24 divisors (see below), whose sum is σ = 2162160. Its totient is φ = 648000.

The previous prime is 1231141. The next prime is 1231171. The reversal of 1231155 is 5511321.

It is not a de Polignac number, because 1231155 - 2⁶ = 1231091 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4780 + ... + 5030.

It is an arithmetic number, because the mean of its divisors is an integer number (90090).

2^1231155 is an apocalyptic number.

1231155 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1231155 is a deficient number, since it is larger than the sum of its proper divisors (931005).

1231155 is a wasteful number, since it uses less digits than its factorization.

1231155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 371 (or 368 counting only the distinct ones).

The product of its digits is 150, while the sum is 18.

The square root of 1231155 is about 1109.5742426715. The cubic root of 1231155 is about 107.1776534600.

Adding to 1231155 its reverse (5511321), we get a palindrome (6742476).

The spelling of 1231155 in words is "one million, two hundred thirty-one thousand, one hundred fifty-five".