561611615501 has 4 divisors (see below), whose sum is σ = 591170121600. Its totient is φ = 532053109404.

The previous prime is 561611615479. The next prime is 561611615563. The reversal of 561611615501 is 105516116165.

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 not a de Polignac number, because 561611615501 - 2⁶ = 561611615437 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561611615701) 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, 14779253021 + ... + 14779253058.

It is an arithmetic number, because the mean of its divisors is an integer number (147792530400).

Almost surely, 2^561611615501 is an apocalyptic number.

It is an amenable number.

561611615501 is a deficient number, since it is larger than the sum of its proper divisors (29558506099).

561611615501 is a wasteful number, since it uses less digits than its factorization.

561611615501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29558506098.

The product of its (nonzero) digits is 27000, while the sum is 38.

The spelling of 561611615501 in words is "five hundred sixty-one billion, six hundred eleven million, six hundred fifteen thousand, five hundred one".