1231616 has 36 divisors (see below), whose sum is σ = 2612232. Its totient is φ = 577536.

The previous prime is 1231613. The next prime is 1231631. The reversal of 1231616 is 6161321.

It is not an unprimeable number, because it can be changed into a prime (1231613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4211 + ... + 4493.

It is an arithmetic number, because the mean of its divisors is an integer number (72562).

2^1231616 is an apocalyptic number.

1231616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1231616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1306116).

1231616 is an abundant number, since it is smaller than the sum of its proper divisors (1380616).

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

1231616 is an equidigital number, since it uses as much as digits as its factorization.

1231616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316 (or 302 counting only the distinct ones).

The product of its digits is 216, while the sum is 20.

The square root of 1231616 is about 1109.7819605670. The cubic root of 1231616 is about 107.1910291743.

Adding to 1231616 its reverse (6161321), we get a palindrome (7392937).

It can be divided in two parts, 1231 and 616, that multiplied together give a triangular number (758296 = T₁₂₃₁).

The spelling of 1231616 in words is "one million, two hundred thirty-one thousand, six hundred sixteen".