1142561 has 4 divisors (see below), whose sum is σ = 1305792. Its totient is φ = 979332.

The previous prime is 1142549. The next prime is 1142569. The reversal of 1142561 is 1652411.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1652411 = 19 ⋅86969.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1142561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1142569) 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, 81605 + ... + 81618.

It is an arithmetic number, because the mean of its divisors is an integer number (326448).

2^1142561 is an apocalyptic number.

It is an amenable number.

1142561 is a deficient number, since it is larger than the sum of its proper divisors (163231).

1142561 is an equidigital number, since it uses as much as digits as its factorization.

1142561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163230.

The product of its digits is 240, while the sum is 20.

The square root of 1142561 is about 1068.9064505372. The cubic root of 1142561 is about 104.5425602911.

Adding to 1142561 its reverse (1652411), we get a palindrome (2794972).

The spelling of 1142561 in words is "one million, one hundred forty-two thousand, five hundred sixty-one".