12019561 has 16 divisors (see below), whose sum is σ = 13272336. Its totient is φ = 10838016.

The previous prime is 12019559. The next prime is 12019577. The reversal of 12019561 is 16591021.

It can be written as a sum of positive squares in 8 ways, for example, as 4648336 + 7371225 = 2156^2 + 2715^2 .

It is a 5-Lehmer number, since φ(12019561) divides (12019561-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 12019561 - 2¹ = 12019559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12019531) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 60915 + ... + 61111.

It is an arithmetic number, because the mean of its divisors is an integer number (829521).

Almost surely, 2^12019561 is an apocalyptic number.

It is an amenable number.

12019561 is a deficient number, since it is larger than the sum of its proper divisors (1252775).

12019561 is a wasteful number, since it uses less digits than its factorization.

12019561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 348.

The product of its (nonzero) digits is 540, while the sum is 25.

The square root of 12019561 is about 3466.9238526394. The cubic root of 12019561 is about 229.0671796190.

The spelling of 12019561 in words is "twelve million, nineteen thousand, five hundred sixty-one".