16645902361 has 27 divisors (see below), whose sum is σ = 18864114717. Its totient is φ = 14677201440.

The previous prime is 16645902331. The next prime is 16645902373. The reversal of 16645902361 is 16320954661.

The square root of 16645902361 is 129019.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 138791961 + 16507110400 = 11781^2 + 128480^2 .

It is not a de Polignac number, because 16645902361 - 2¹⁵ = 16645869593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16645902331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 52510575 + ... + 52510891.

Almost surely, 2^16645902361 is an apocalyptic number.

16645902361 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

16645902361 is the 129019-th square number.

16645902361 is the 64510-th centered octagonal number.

It is an amenable number.

16645902361 is a deficient number, since it is larger than the sum of its proper divisors (2218212356).

16645902361 is an frugal number, since it uses more digits than its factorization.

16645902361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 730 (or 365 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 43.

The spelling of 16645902361 in words is "sixteen billion, six hundred forty-five million, nine hundred two thousand, three hundred sixty-one".