661746836829 has 8 divisors (see below), whose sum is σ = 950200586272. Its totient is φ = 407228822640.

The previous prime is 661746836827. The next prime is 661746836843. The reversal of 661746836829 is 928638647166.

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

It is not a de Polignac number, because 661746836829 - 2¹ = 661746836827 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 661746836829.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661746836827) 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, 8483933767 + ... + 8483933844.

It is an arithmetic number, because the mean of its divisors is an integer number (118775073284).

Almost surely, 2^661746836829 is an apocalyptic number.

It is an amenable number.

661746836829 is a deficient number, since it is larger than the sum of its proper divisors (288453749443).

661746836829 is a wasteful number, since it uses less digits than its factorization.

661746836829 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16967867627.

The product of its digits is 125411328, while the sum is 66.

The spelling of 661746836829 in words is "six hundred sixty-one billion, seven hundred forty-six million, eight hundred thirty-six thousand, eight hundred twenty-nine".