665149381784 has 32 divisors (see below), whose sum is σ = 1249481708640. Its totient is φ = 331954560000.

The previous prime is 665149381753. The next prime is 665149381817. The reversal of 665149381784 is 487183941566.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 20180582 + ... + 20213514.

It is an arithmetic number, because the mean of its divisors is an integer number (39046303395).

Almost surely, 2^665149381784 is an apocalyptic number.

It is an amenable number.

665149381784 is a deficient number, since it is larger than the sum of its proper divisors (584332326856).

665149381784 is a wasteful number, since it uses less digits than its factorization.

665149381784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37571 (or 37567 counting only the distinct ones).

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

The spelling of 665149381784 in words is "six hundred sixty-five billion, one hundred forty-nine million, three hundred eighty-one thousand, seven hundred eighty-four".