661845548166 has 32 divisors (see below), whose sum is σ = 1483054403328. Its totient is φ = 195138735840.

The previous prime is 661845548141. The next prime is 661845548201.

It is a happy number.

661845548166 is nontrivially palindromic in base 10.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135510570 + ... + 135515453.

It is an arithmetic number, because the mean of its divisors is an integer number (46345450104).

Almost surely, 2^661845548166 is an apocalyptic number.

661845548166 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

661845548166 is an abundant number, since it is smaller than the sum of its proper divisors (821208855162).

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

661845548166 is a wasteful number, since it uses less digits than its factorization.

661845548166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271026076.

The product of its digits is 33177600, while the sum is 60.

The spelling of 661845548166 in words is "six hundred sixty-one billion, eight hundred forty-five million, five hundred forty-eight thousand, one hundred sixty-six".