61664595587 has 4 divisors (see below), whose sum is σ = 70473823536. Its totient is φ = 52855367640.

The previous prime is 61664595491. The next prime is 61664595599. The reversal of 61664595587 is 78559546616.

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

It is a cyclic number.

It is not a de Polignac number, because 61664595587 - 2⁸ = 61664595331 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61664595887) 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, 4404613964 + ... + 4404613977.

It is an arithmetic number, because the mean of its divisors is an integer number (17618455884).

Almost surely, 2^61664595587 is an apocalyptic number.

61664595587 is a deficient number, since it is larger than the sum of its proper divisors (8809227949).

61664595587 is an equidigital number, since it uses as much as digits as its factorization.

61664595587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8809227948.

The product of its digits is 54432000, while the sum is 62.

The spelling of 61664595587 in words is "sixty-one billion, six hundred sixty-four million, five hundred ninety-five thousand, five hundred eighty-seven".