561401 has 4 divisors (see below), whose sum is σ = 576612. Its totient is φ = 546192.

The previous prime is 561389. The next prime is 561409. The reversal of 561401 is 104165.

It is a happy number.

561401 is nontrivially palindromic in base 15.

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 511225 + 50176 = 715^2 + 224^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-561401 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 561401.

It is not an unprimeable number, because it can be changed into a prime (561409) 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, 7550 + ... + 7623.

It is an arithmetic number, because the mean of its divisors is an integer number (144153).

2⁵⁶¹⁴⁰¹ is an apocalyptic number.

561401 is the 401-st centered heptagonal number.

It is an amenable number.

561401 is a deficient number, since it is larger than the sum of its proper divisors (15211).

561401 is a wasteful number, since it uses less digits than its factorization.

561401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15210.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 561401 is about 749.2669751163. The cubic root of 561401 is about 82.4943859051.

Adding to 561401 its reverse (104165), we get a palindrome (665566).

The spelling of 561401 in words is "five hundred sixty-one thousand, four hundred one".