661769728357 has 8 divisors (see below), whose sum is σ = 703362820160. Its totient is φ = 620852947200.

The previous prime is 661769728351. The next prime is 661769728363. The reversal of 661769728357 is 753827967166.

It is an interprime number because it is at equal distance from previous prime (661769728351) and next prime (661769728363).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 661769728357 - 2¹¹ = 661769726309 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 661769728292 and 661769728301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661769728351) 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, 169075644 + ... + 169079557.

It is an arithmetic number, because the mean of its divisors is an integer number (87920352520).

Almost surely, 2^661769728357 is an apocalyptic number.

It is an amenable number.

661769728357 is a deficient number, since it is larger than the sum of its proper divisors (41593091803).

661769728357 is a wasteful number, since it uses less digits than its factorization.

661769728357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338155323.

The product of its digits is 160030080, while the sum is 67.

The spelling of 661769728357 in words is "six hundred sixty-one billion, seven hundred sixty-nine million, seven hundred twenty-eight thousand, three hundred fifty-seven".