1231660 has 12 divisors (see below), whose sum is σ = 2586528. Its totient is φ = 492656.

The previous prime is 1231631. The next prime is 1231663. The reversal of 1231660 is 661321.

1231660 is nontrivially palindromic in base 8.

1231660 is an esthetic number in base 8, because in such base its adjacent digits differ by 1.

It is an Ulam number.

1231660 is an undulating number in base 8.

It is not an unprimeable number, because it can be changed into a prime (1231663) 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, 30772 + ... + 30811.

It is an arithmetic number, because the mean of its divisors is an integer number (215544).

2^1231660 is an apocalyptic number.

1231660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1231660 is an abundant number, since it is smaller than the sum of its proper divisors (1354868).

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

1231660 is a wasteful number, since it uses less digits than its factorization.

1231660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61592 (or 61590 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 1231660 is about 1109.8017841038. The cubic root of 1231660 is about 107.1923056407.

Adding to 1231660 its reverse (661321), we get a palindrome (1892981).

It can be divided in two parts, 1231 and 660, that added together give a triangular number (1891 = T₆₁).

The spelling of 1231660 in words is "one million, two hundred thirty-one thousand, six hundred sixty".