660616791 has 4 divisors (see below), whose sum is σ = 880822392. Its totient is φ = 440411192.

The previous prime is 660616771. The next prime is 660616811. The reversal of 660616791 is 197616066.

660616791 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 an interprime number because it is at equal distance from previous prime (660616771) and next prime (660616811).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-660616791 is a prime.

It is a super-2 number, since 2×660616791² = 872829089102275362, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660616771) 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, 110102796 + ... + 110102801.

It is an arithmetic number, because the mean of its divisors is an integer number (220205598).

Almost surely, 2^660616791 is an apocalyptic number.

660616791 is a deficient number, since it is larger than the sum of its proper divisors (220205601).

660616791 is a wasteful number, since it uses less digits than its factorization.

660616791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220205600.

The product of its (nonzero) digits is 81648, while the sum is 42.

The square root of 660616791 is about 25702.4666326016. The cubic root of 660616791 is about 870.9299041143.

The spelling of 660616791 in words is "six hundred sixty million, six hundred sixteen thousand, seven hundred ninety-one".