561213431 has 4 divisors (see below), whose sum is σ = 590751000. Its totient is φ = 531675864.

The previous prime is 561213407. The next prime is 561213451. The reversal of 561213431 is 134312165.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-561213431 is a prime.

It is a super-2 number, since 2×561213431² = 629921030269583522, which contains 22 as substring.

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 561213431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561213451) 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, 14768756 + ... + 14768793.

It is an arithmetic number, because the mean of its divisors is an integer number (147687750).

Almost surely, 2^561213431 is an apocalyptic number.

561213431 is a deficient number, since it is larger than the sum of its proper divisors (29537569).

561213431 is a wasteful number, since it uses less digits than its factorization.

561213431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29537568.

The product of its digits is 2160, while the sum is 26.

The square root of 561213431 is about 23689.9436681475. The cubic root of 561213431 is about 824.8519751565.

Adding to 561213431 its reverse (134312165), we get a palindrome (695525596).

It can be divided in two parts, 5612134 and 31, that added together give a palindrome (5612165).

The spelling of 561213431 in words is "five hundred sixty-one million, two hundred thirteen thousand, four hundred thirty-one".