431561 has 8 divisors (see below), whose sum is σ = 471240. Its totient is φ = 392832.

The previous prime is 431533. The next prime is 431567. The reversal of 431561 is 165134.

It can be written as a sum of positive squares in 4 ways, for example, as 1225 + 430336 = 35^2 + 656^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-431561 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (431567) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 971 + ... + 1343.

It is an arithmetic number, because the mean of its divisors is an integer number (58905).

2⁴³¹⁵⁶¹ is an apocalyptic number.

It is an amenable number.

431561 is a deficient number, since it is larger than the sum of its proper divisors (39679).

431561 is a wasteful number, since it uses less digits than its factorization.

431561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 475.

The product of its digits is 360, while the sum is 20.

The square root of 431561 is about 656.9330255056. The cubic root of 431561 is about 75.5696475862.

Adding to 431561 its reverse (165134), we get a palindrome (596695).

The spelling of 431561 in words is "four hundred thirty-one thousand, five hundred sixty-one".