661445452 has 12 divisors (see below), whose sum is σ = 1225619640. Its totient is φ = 311268416.

The previous prime is 661445381. The next prime is 661445471. The reversal of 661445452 is 254544166.

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 3 ways as a sum of consecutive naturals, for example, 4863502 + ... + 4863637.

It is an arithmetic number, because the mean of its divisors is an integer number (102134970).

Almost surely, 2^661445452 is an apocalyptic number.

It is an amenable number.

661445452 is a deficient number, since it is larger than the sum of its proper divisors (564174188).

661445452 is a wasteful number, since it uses less digits than its factorization.

661445452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9727160 (or 9727158 counting only the distinct ones).

The product of its digits is 115200, while the sum is 37.

The square root of 661445452 is about 25718.5818427066. The cubic root of 661445452 is about 871.2939094409.

The spelling of 661445452 in words is "six hundred sixty-one million, four hundred forty-five thousand, four hundred fifty-two".