661005666150 has 96 divisors (see below), whose sum is σ = 1649702412288. Its totient is φ = 175151059200.

The previous prime is 661005666107. The next prime is 661005666151. The reversal of 661005666150 is 51666500166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661005666151) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 26832739 + ... + 26857361.

It is an arithmetic number, because the mean of its divisors is an integer number (17184400128).

Almost surely, 2^661005666150 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661005666150, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (824851206144).

661005666150 is an abundant number, since it is smaller than the sum of its proper divisors (988696746138).

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

661005666150 is a wasteful number, since it uses less digits than its factorization.

661005666150 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25766 (or 25761 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 42.

The spelling of 661005666150 in words is "six hundred sixty-one billion, five million, six hundred sixty-six thousand, one hundred fifty".