1666616065650 has 96 divisors (see below), whose sum is σ = 4716573655680. Its totient is φ = 432419290560.

The previous prime is 1666616065649. The next prime is 1666616065657. The reversal of 1666616065650 is 565606166661.

It is a super-2 number, since 2×1666616065650² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (1666616065657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 16632894 + ... + 16732793.

It is an arithmetic number, because the mean of its divisors is an integer number (49130975580).

Almost surely, 2^{1666616065650} is an apocalyptic number.

1666616065650 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1666616065650 is an abundant number, since it is smaller than the sum of its proper divisors (3049957590030).

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

1666616065650 is a wasteful number, since it uses less digits than its factorization.

1666616065650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33365745 (or 33365734 counting only the distinct ones).

The product of its (nonzero) digits is 6998400, while the sum is 54.

The spelling of 1666616065650 in words is "one trillion, six hundred sixty-six billion, six hundred sixteen million, sixty-five thousand, six hundred fifty".