661352764 has 24 divisors (see below), whose sum is σ = 1208678688. Its totient is φ = 316039680.

The previous prime is 661352761. The next prime is 661352767. The reversal of 661352764 is 467253166.

It is an interprime number because it is at equal distance from previous prime (661352761) and next prime (661352767).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661352761) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 156244 + ... + 160420.

It is an arithmetic number, because the mean of its divisors is an integer number (50361612).

Almost surely, 2^661352764 is an apocalyptic number.

It is an amenable number.

661352764 is a deficient number, since it is larger than the sum of its proper divisors (547325924).

661352764 is a wasteful number, since it uses less digits than its factorization.

661352764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5925 (or 5923 counting only the distinct ones).

The product of its digits is 181440, while the sum is 40.

The square root of 661352764 is about 25716.7798139658. The cubic root of 661352764 is about 871.2532095554.

The spelling of 661352764 in words is "six hundred sixty-one million, three hundred fifty-two thousand, seven hundred sixty-four".