661985874413 has 8 divisors (see below), whose sum is σ = 663454782432. Its totient is φ = 660517186896.

The previous prime is 661985874373. The next prime is 661985874421. The reversal of 661985874413 is 314478589166.

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

It is a cyclic number.

It is not a de Polignac number, because 661985874413 - 2⁶ = 661985874349 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661985874463) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6932831 + ... + 7027667.

It is an arithmetic number, because the mean of its divisors is an integer number (82931847804).

Almost surely, 2^661985874413 is an apocalyptic number.

It is an amenable number.

661985874413 is a deficient number, since it is larger than the sum of its proper divisors (1468908019).

661985874413 is a wasteful number, since it uses less digits than its factorization.

661985874413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110251.

The product of its digits is 34836480, while the sum is 62.

The spelling of 661985874413 in words is "six hundred sixty-one billion, nine hundred eighty-five million, eight hundred seventy-four thousand, four hundred thirteen".