561642877 has 4 divisors (see below), whose sum is σ = 565006176. Its totient is φ = 558279580.

The previous prime is 561642859. The next prime is 561642919. The reversal of 561642877 is 778246165.

It is a happy number.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-561642877 is a prime.

It is a super-3 number, since 3×561642877³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561642817) 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, 1681399 + ... + 1681732.

It is an arithmetic number, because the mean of its divisors is an integer number (141251544).

Almost surely, 2^561642877 is an apocalyptic number.

It is an amenable number.

561642877 is a deficient number, since it is larger than the sum of its proper divisors (3363299).

561642877 is a wasteful number, since it uses less digits than its factorization.

561642877 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3363298.

The product of its digits is 564480, while the sum is 46.

The square root of 561642877 is about 23699.0058230298. The cubic root of 561642877 is about 825.0623164437.

The spelling of 561642877 in words is "five hundred sixty-one million, six hundred forty-two thousand, eight hundred seventy-seven".