7145561 has 4 divisors (see below), whose sum is σ = 7165092. Its totient is φ = 7126032.

The previous prime is 7145557. The next prime is 7145563. The reversal of 7145561 is 1655417.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1655417 = 37 ⋅44741.

It can be written as a sum of positive squares in 2 ways, for example, as 1651225 + 5494336 = 1285^2 + 2344^2 .

It is a cyclic number.

It is not a de Polignac number, because 7145561 - 2² = 7145557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7145563) 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, 9206 + ... + 9951.

It is an arithmetic number, because the mean of its divisors is an integer number (1791273).

Almost surely, 2^7145561 is an apocalyptic number.

It is an amenable number.

7145561 is a deficient number, since it is larger than the sum of its proper divisors (19531).

7145561 is a wasteful number, since it uses less digits than its factorization.

7145561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19530.

The product of its digits is 4200, while the sum is 29.

The square root of 7145561 is about 2673.1182166152. The cubic root of 7145561 is about 192.6099759508.

The spelling of 7145561 in words is "seven million, one hundred forty-five thousand, five hundred sixty-one".