561612147567781 has 4 divisors (see below), whose sum is σ = 562384653961312. Its totient is φ = 560839641174252.

The previous prime is 561612147567739. The next prime is 561612147567881. The reversal of 561612147567781 is 187765741216165.

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 not a de Polignac number, because 561612147567781 - 2⁴⁵ = 526427775478949 is a prime.

It is a super-2 number, since 2×561612147567781² (a number of 30 digits) contains 22 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 (561612147567881) 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, 386253195675 + ... + 386253197128.

It is an arithmetic number, because the mean of its divisors is an integer number (140596163490328).

Almost surely, 2^{561612147567781} is an apocalyptic number.

It is an amenable number.

561612147567781 is a deficient number, since it is larger than the sum of its proper divisors (772506393531).

561612147567781 is an equidigital number, since it uses as much as digits as its factorization.

561612147567781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 772506393530.

The product of its digits is 118540800, while the sum is 67.

The spelling of 561612147567781 in words is "five hundred sixty-one trillion, six hundred twelve billion, one hundred forty-seven million, five hundred sixty-seven thousand, seven hundred eighty-one".