661061162020 has 96 divisors (see below), whose sum is σ = 1608356445696. Its totient is φ = 223550976000.

The previous prime is 661061162017. The next prime is 661061162051. The reversal of 661061162020 is 20261160166.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 3629940 + ... + 3807700.

It is an arithmetic number, because the mean of its divisors is an integer number (16753712976).

Almost surely, 2^661061162020 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661061162020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (804178222848).

661061162020 is an abundant number, since it is smaller than the sum of its proper divisors (947295283676).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661061162020 is a wasteful number, since it uses less digits than its factorization.

661061162020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178141 (or 178139 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 31.

The spelling of 661061162020 in words is "six hundred sixty-one billion, sixty-one million, one hundred sixty-two thousand, twenty".