660605515651 has 4 divisors (see below), whose sum is σ = 660611043400. Its totient is φ = 660599987904.

The previous prime is 660605515607. The next prime is 660605515663. The reversal of 660605515651 is 156515506066.

660605515651 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 660605515651 - 2¹³ = 660605507459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (660605515681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2580561 + ... + 2824978.

It is an arithmetic number, because the mean of its divisors is an integer number (165152760850).

Almost surely, 2^660605515651 is an apocalyptic number.

660605515651 is a deficient number, since it is larger than the sum of its proper divisors (5527749).

660605515651 is a wasteful number, since it uses less digits than its factorization.

660605515651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5527748.

The product of its (nonzero) digits is 810000, while the sum is 46.

The spelling of 660605515651 in words is "six hundred sixty billion, six hundred five million, five hundred fifteen thousand, six hundred fifty-one".