1605665606650 has 36 divisors (see below), whose sum is σ = 3474136079118. Its totient is φ = 550513921440.

The previous prime is 1605665606627. The next prime is 1605665606681. The reversal of 1605665606650 is 566065665061.

It can be written as a sum of positive squares in 3 ways, for example, as 816053869449 + 789611737201 = 903357^2 + 888601^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 327684409 + ... + 327689308.

Almost surely, 2^{1605665606650} is an apocalyptic number.

1605665606650 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1605665606650 is an abundant number, since it is smaller than the sum of its proper divisors (1868470472468).

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

1605665606650 is a wasteful number, since it uses less digits than its factorization.

1605665606650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 655373743 (or 655373731 counting only the distinct ones).

The product of its (nonzero) digits is 5832000, while the sum is 52.

The spelling of 1605665606650 in words is "one trillion, six hundred five billion, six hundred sixty-five million, six hundred six thousand, six hundred fifty".