663172342520 has 64 divisors (see below), whose sum is σ = 1508327399520. Its totient is φ = 262398173184.

The previous prime is 663172342499. The next prime is 663172342529. The reversal of 663172342520 is 25243271366.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663172342529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2765324 + ... + 2995556.

Almost surely, 2^663172342520 is an apocalyptic number.

It is an amenable number.

663172342520 is an abundant number, since it is smaller than the sum of its proper divisors (845155057000).

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

663172342520 is a wasteful number, since it uses less digits than its factorization.

663172342520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231024 (or 231020 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 41.

The spelling of 663172342520 in words is "six hundred sixty-three billion, one hundred seventy-two million, three hundred forty-two thousand, five hundred twenty".