661083660540 has 96 divisors (see below), whose sum is σ = 2081484437760. Its totient is φ = 174165000768.

The previous prime is 661083660529. The next prime is 661083660541. The reversal of 661083660540 is 45066380166.

661083660540 is a `hidden beast` number, since 6 + 6 + 1 + 0 + 8 + 36 + 605 + 4 + 0 = 666.

661083660540 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661083660541) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7330054 + ... + 7419693.

It is an arithmetic number, because the mean of its divisors is an integer number (21682129560).

Almost surely, 2^661083660540 is an apocalyptic number.

661083660540 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

661083660540 is an abundant number, since it is smaller than the sum of its proper divisors (1420400777220).

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

661083660540 is a wasteful number, since it uses less digits than its factorization.

661083660540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14749848 (or 14749840 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The spelling of 661083660540 in words is "six hundred sixty-one billion, eighty-three million, six hundred sixty thousand, five hundred forty".