61630645666 has 16 divisors (see below), whose sum is σ = 97919670744. Its totient is φ = 28992077824.

The previous prime is 61630645613. The next prime is 61630645669. The reversal of 61630645666 is 66654603616.

It can be written as a sum of positive squares in 4 ways, for example, as 59362886025 + 2267759641 = 243645^2 + 47621^2 .

It is not an unprimeable number, because it can be changed into a prime (61630645669) 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, 235615 + ... + 422818.

Almost surely, 2^61630645666 is an apocalyptic number.

61630645666 is a deficient number, since it is larger than the sum of its proper divisors (36289025078).

61630645666 is a wasteful number, since it uses less digits than its factorization.

61630645666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661205.

The product of its (nonzero) digits is 2799360, while the sum is 49.

The spelling of 61630645666 in words is "sixty-one billion, six hundred thirty million, six hundred forty-five thousand, six hundred sixty-six".