665079516240 has 80 divisors (see below), whose sum is σ = 2062944385728. Its totient is φ = 177251493888.

The previous prime is 665079516239. The next prime is 665079516251. The reversal of 665079516240 is 42615970566.

It is a tau number, because it is divible by the number of its divisors (80).

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 390649 + ... + 1217688.

Almost surely, 2^665079516240 is an apocalyptic number.

665079516240 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

665079516240 is an abundant number, since it is smaller than the sum of its proper divisors (1397864869488).

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

665079516240 is a wasteful number, since it uses less digits than its factorization.

665079516240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1610076 (or 1610070 counting only the distinct ones).

The product of its (nonzero) digits is 2721600, while the sum is 51.

The spelling of 665079516240 in words is "six hundred sixty-five billion, seventy-nine million, five hundred sixteen thousand, two hundred forty".