561276781 has 8 divisors (see below), whose sum is σ = 604638720. Its totient is φ = 517941552.

The previous prime is 561276733. The next prime is 561276803. The reversal of 561276781 is 187672165.

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

It is a cyclic number.

It is not a de Polignac number, because 561276781 - 2¹¹ = 561274733 is a prime.

It is a super-2 number, since 2×561276781² = 630063249779443922, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561276581) 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, 67836 + ... + 75658.

It is an arithmetic number, because the mean of its divisors is an integer number (75579840).

Almost surely, 2^561276781 is an apocalyptic number.

It is an amenable number.

561276781 is a deficient number, since it is larger than the sum of its proper divisors (43361939).

561276781 is a wasteful number, since it uses less digits than its factorization.

561276781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13355.

The product of its digits is 141120, while the sum is 43.

The square root of 561276781 is about 23691.2806956483. The cubic root of 561276781 is about 824.8830105307.

The spelling of 561276781 in words is "five hundred sixty-one million, two hundred seventy-six thousand, seven hundred eighty-one".