661895461288 has 16 divisors (see below), whose sum is σ = 1241162239680. Its totient is φ = 330918864048.

The previous prime is 661895461273. The next prime is 661895461291. The reversal of 661895461288 is 882164598166.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3510720 + ... + 3694447.

It is an arithmetic number, because the mean of its divisors is an integer number (77572639980).

Almost surely, 2^661895461288 is an apocalyptic number.

It is an amenable number.

661895461288 is a deficient number, since it is larger than the sum of its proper divisors (579266778392).

661895461288 is a wasteful number, since it uses less digits than its factorization.

661895461288 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7216656 (or 7216652 counting only the distinct ones).

The product of its digits is 39813120, while the sum is 64.

The spelling of 661895461288 in words is "six hundred sixty-one billion, eight hundred ninety-five million, four hundred sixty-one thousand, two hundred eighty-eight".