61515666664988 has 12 divisors (see below), whose sum is σ = 107785157010552. Its totient is φ = 30719907519120.

The previous prime is 61515666664981. The next prime is 61515666664993. The reversal of 61515666664988 is 88946666651516.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61515666664981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9481449695 + ... + 9481456182.

It is an arithmetic number, because the mean of its divisors is an integer number (8982096417546).

Almost surely, 2^{61515666664988} is an apocalyptic number.

It is an amenable number.

61515666664988 is a deficient number, since it is larger than the sum of its proper divisors (46269490345564).

61515666664988 is a wasteful number, since it uses less digits than its factorization.

61515666664988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18962906692 (or 18962906690 counting only the distinct ones).

The product of its digits is 2687385600, while the sum is 77.

The spelling of 61515666664988 in words is "sixty-one trillion, five hundred fifteen billion, six hundred sixty-six million, six hundred sixty-four thousand, nine hundred eighty-eight".