61666687458 has 24 divisors (see below), whose sum is σ = 134310698496. Its totient is φ = 20447940600.

The previous prime is 61666687363. The next prime is 61666687531. The reversal of 61666687458 is 85478666616.

It is a junction number, because it is equal to n+sod(n) for n = 61666687395 and 61666687404.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8964958 + ... + 8971833.

It is an arithmetic number, because the mean of its divisors is an integer number (5596279104).

Almost surely, 2^61666687458 is an apocalyptic number.

61666687458 is an abundant number, since it is smaller than the sum of its proper divisors (72644011038).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61666687458 is a wasteful number, since it uses less digits than its factorization.

61666687458 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17936990 (or 17936987 counting only the distinct ones).

The product of its digits is 69672960, while the sum is 63.

The spelling of 61666687458 in words is "sixty-one billion, six hundred sixty-six million, six hundred eighty-seven thousand, four hundred fifty-eight".