1231556 has 12 divisors (see below), whose sum is σ = 2170560. Its totient is φ = 611400.

The previous prime is 1231553. The next prime is 1231577. The reversal of 1231556 is 6551321.

It is a super-2 number, since 2×1231556² = 3033460362272, which contains 22 as substring.

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (1231553) 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, 416 + ... + 1623.

It is an arithmetic number, because the mean of its divisors is an integer number (180880).

2^1231556 is an apocalyptic number.

It is an amenable number.

1231556 is a deficient number, since it is larger than the sum of its proper divisors (939004).

1231556 is a wasteful number, since it uses less digits than its factorization.

1231556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2194 (or 2192 counting only the distinct ones).

The product of its digits is 900, while the sum is 23.

The square root of 1231556 is about 1109.7549279008. The cubic root of 1231556 is about 107.1892884894.

Adding to 1231556 its reverse (6551321), we get a palindrome (7782877).

The spelling of 1231556 in words is "one million, two hundred thirty-one thousand, five hundred fifty-six".