616562561 has 4 divisors (see below), whose sum is σ = 633226452. Its totient is φ = 599898672.

The previous prime is 616562549. The next prime is 616562581. The reversal of 616562561 is 165265616.

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

It can be written as a sum of positive squares in 2 ways, for example, as 336502336 + 280060225 = 18344^2 + 16735^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-616562561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (616562581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8331890 + ... + 8331963.

It is an arithmetic number, because the mean of its divisors is an integer number (158306613).

Almost surely, 2^616562561 is an apocalyptic number.

It is an amenable number.

616562561 is a deficient number, since it is larger than the sum of its proper divisors (16663891).

616562561 is a wasteful number, since it uses less digits than its factorization.

616562561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16663890.

The product of its digits is 64800, while the sum is 38.

The square root of 616562561 is about 24830.6778199871. The cubic root of 616562561 is about 851.1231109890.

The spelling of 616562561 in words is "six hundred sixteen million, five hundred sixty-two thousand, five hundred sixty-one".