661025550325 has 48 divisors (see below), whose sum is σ = 952086491136. Its totient is φ = 445894848000.

The previous prime is 661025550323. The next prime is 661025550343. The reversal of 661025550325 is 523055520166.

It is a happy number.

It is not a de Polignac number, because 661025550325 - 2¹ = 661025550323 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 (661025550323) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 4825275 + ... + 4960375.

It is an arithmetic number, because the mean of its divisors is an integer number (19835135232).

Almost surely, 2^661025550325 is an apocalyptic number.

It is an amenable number.

661025550325 is a deficient number, since it is larger than the sum of its proper divisors (291060940811).

661025550325 is a wasteful number, since it uses less digits than its factorization.

661025550325 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135574 (or 135569 counting only the distinct ones).

The product of its (nonzero) digits is 270000, while the sum is 40.

The spelling of 661025550325 in words is "six hundred sixty-one billion, twenty-five million, five hundred fifty thousand, three hundred twenty-five".