661510511606 has 16 divisors (see below), whose sum is σ = 1150943663616. Its totient is φ = 279273094056.

The previous prime is 661510511603. The next prime is 661510511617. The reversal of 661510511606 is 606115015166.

661510511606 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 661510511606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661510511603) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 352616606 + ... + 352618481.

It is an arithmetic number, because the mean of its divisors is an integer number (71933978976).

Almost surely, 2^661510511606 is an apocalyptic number.

661510511606 is a deficient number, since it is larger than the sum of its proper divisors (489433152010).

661510511606 is a wasteful number, since it uses less digits than its factorization.

661510511606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 705235163.

The product of its (nonzero) digits is 32400, while the sum is 38.

The spelling of 661510511606 in words is "six hundred sixty-one billion, five hundred ten million, five hundred eleven thousand, six hundred six".