16646405880395 has 4 divisors (see below), whose sum is σ = 19975687056480. Its totient is φ = 13317124704312.

The previous prime is 16646405880389. The next prime is 16646405880449. The reversal of 16646405880395 is 59308850464661.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 16646405880395 - 2⁶ = 16646405880331 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1664640588035 + ... + 1664640588044.

It is an arithmetic number, because the mean of its divisors is an integer number (4993921764120).

Almost surely, 2^{16646405880395} is an apocalyptic number.

16646405880395 is a deficient number, since it is larger than the sum of its proper divisors (3329281176085).

16646405880395 is an equidigital number, since it uses as much as digits as its factorization.

16646405880395 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3329281176084.

The product of its (nonzero) digits is 149299200, while the sum is 65.

The spelling of 16646405880395 in words is "sixteen trillion, six hundred forty-six billion, four hundred five million, eight hundred eighty thousand, three hundred ninety-five".