561157 has 4 divisors (see below), whose sum is σ = 563436. Its totient is φ = 558880.

The previous prime is 561109. The next prime is 561161. The reversal of 561157 is 751165.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 159201 + 401956 = 399^2 + 634^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-561157 is a prime.

It is a Duffinian number.

561157 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (501157) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 718 + ... + 1279.

It is an arithmetic number, because the mean of its divisors is an integer number (140859).

2⁵⁶¹¹⁵⁷ is an apocalyptic number.

It is an amenable number.

561157 is a deficient number, since it is larger than the sum of its proper divisors (2279).

561157 is a wasteful number, since it uses less digits than its factorization.

561157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2278.

The product of its digits is 1050, while the sum is 25.

The square root of 561157 is about 749.1041316132. The cubic root of 561157 is about 82.4824327456.

The spelling of 561157 in words is "five hundred sixty-one thousand, one hundred fifty-seven".