661953325 has 12 divisors (see below), whose sum is σ = 895442688. Its totient is φ = 481420400.

The previous prime is 661953307. The next prime is 661953343. The reversal of 661953325 is 523359166.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (661953307) and next prime (661953343).

It is not a de Polignac number, because 661953325 - 2⁹ = 661952813 is a prime.

It is a Duffinian number.

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 11 ways as a sum of consecutive naturals, for example, 1203277 + ... + 1203826.

It is an arithmetic number, because the mean of its divisors is an integer number (74620224).

Almost surely, 2^661953325 is an apocalyptic number.

It is an amenable number.

661953325 is a deficient number, since it is larger than the sum of its proper divisors (233489363).

661953325 is a wasteful number, since it uses less digits than its factorization.

661953325 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2407124 (or 2407119 counting only the distinct ones).

The product of its digits is 145800, while the sum is 40.

The square root of 661953325 is about 25728.4536068532. The cubic root of 661953325 is about 871.5168522112.

The spelling of 661953325 in words is "six hundred sixty-one million, nine hundred fifty-three thousand, three hundred twenty-five".