1581168 has 20 divisors (see below), whose sum is σ = 4084808. Its totient is φ = 527040.

The previous prime is 1581163. The next prime is 1581169. The reversal of 1581168 is 8611851.

It is a happy number.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1581163) 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, 16423 + ... + 16518.

2^1581168 is an apocalyptic number.

It is an amenable number.

1581168 is an abundant number, since it is smaller than the sum of its proper divisors (2503640).

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

1581168 is a wasteful number, since it uses less digits than its factorization.

1581168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32952 (or 32946 counting only the distinct ones).

The product of its digits is 1920, while the sum is 30.

The square root of 1581168 is about 1257.4450286195. The cubic root of 1581168 is about 116.5000214899.

It can be divided in two parts, 158 and 1168, that added together give a triangular number (1326 = T₅₁).

The spelling of 1581168 in words is "one million, five hundred eighty-one thousand, one hundred sixty-eight".