661605496 has 8 divisors (see below), whose sum is σ = 1240510320. Its totient is φ = 330802744.

The previous prime is 661605493. The next prime is 661605521. The reversal of 661605496 is 694506166.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661605493) 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 as a sum of consecutive naturals, namely, 41350336 + ... + 41350351.

It is an arithmetic number, because the mean of its divisors is an integer number (155063790).

Almost surely, 2^661605496 is an apocalyptic number.

It is an amenable number.

661605496 is a deficient number, since it is larger than the sum of its proper divisors (578904824).

661605496 is a wasteful number, since it uses less digits than its factorization.

661605496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82700693 (or 82700689 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 43.

The square root of 661605496 is about 25721.6931013493. The cubic root of 661605496 is about 871.3641768211.

The spelling of 661605496 in words is "six hundred sixty-one million, six hundred five thousand, four hundred ninety-six".