40491616565 has 8 divisors (see below), whose sum is σ = 48944611800. Its totient is φ = 32156845312.

The previous prime is 40491616559. The next prime is 40491616577. The reversal of 40491616565 is 56561619404.

It can be written as a sum of positive squares in 4 ways, for example, as 1157224324 + 39334392241 = 34018^2 + 198329^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40491616565 is a prime.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 29555240 + ... + 29556609.

It is an arithmetic number, because the mean of its divisors is an integer number (6118076475).

Almost surely, 2^40491616565 is an apocalyptic number.

It is an amenable number.

40491616565 is a deficient number, since it is larger than the sum of its proper divisors (8452995235).

40491616565 is a wasteful number, since it uses less digits than its factorization.

40491616565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59111991.

The product of its (nonzero) digits is 777600, while the sum is 47.

The spelling of 40491616565 in words is "forty billion, four hundred ninety-one million, six hundred sixteen thousand, five hundred sixty-five".