4157561 has 4 divisors (see below), whose sum is σ = 4376400. Its totient is φ = 3938724.

The previous prime is 4157513. The next prime is 4157563. The reversal of 4157561 is 1657514.

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: 1657514 = 2 ⋅828757.

It is a cyclic number.

It is not a de Polignac number, because 4157561 - 2¹⁴ = 4141177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4157563) 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, 109391 + ... + 109428.

It is an arithmetic number, because the mean of its divisors is an integer number (1094100).

Almost surely, 2^4157561 is an apocalyptic number.

It is an amenable number.

4157561 is a deficient number, since it is larger than the sum of its proper divisors (218839).

4157561 is a wasteful number, since it uses less digits than its factorization.

4157561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218838.

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

The square root of 4157561 is about 2039.0098087062. The cubic root of 4157561 is about 160.7975929485.

The spelling of 4157561 in words is "four million, one hundred fifty-seven thousand, five hundred sixty-one".