1581696 has 48 divisors (see below), whose sum is σ = 4554810. Its totient is φ = 526848.

The previous prime is 1581673. The next prime is 1581707. The reversal of 1581696 is 6961851.

It can be written as a sum of positive squares in only one way, i.e., 876096 + 705600 = 936^2 + 840^2 .

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 1581696.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 466 + ... + 1838.

2^1581696 is an apocalyptic number.

1581696 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 1581696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2277405).

1581696 is an abundant number, since it is smaller than the sum of its proper divisors (2973114).

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

1581696 is a wasteful number, since it uses less digits than its factorization.

1581696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1393 (or 1378 counting only the distinct ones).

The product of its digits is 12960, while the sum is 36.

The square root of 1581696 is about 1257.6549606311. The cubic root of 1581696 is about 116.5129876781.

The spelling of 1581696 in words is "one million, five hundred eighty-one thousand, six hundred ninety-six".