16642655405 has 4 divisors (see below), whose sum is σ = 19971186492. Its totient is φ = 13314124320.

The previous prime is 16642655377. The next prime is 16642655527. The reversal of 16642655405 is 50455624661.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4235146084 + 12407509321 = 65078^2 + 111389^2 .

It is not a de Polignac number, because 16642655405 - 2¹⁰ = 16642654381 is a prime.

It is a Duffinian number.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 1664265536 + ... + 1664265545.

It is an arithmetic number, because the mean of its divisors is an integer number (4992796623).

Almost surely, 2^16642655405 is an apocalyptic number.

It is an amenable number.

16642655405 is a deficient number, since it is larger than the sum of its proper divisors (3328531087).

16642655405 is an equidigital number, since it uses as much as digits as its factorization.

16642655405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3328531086.

The product of its (nonzero) digits is 864000, while the sum is 44.

The spelling of 16642655405 in words is "sixteen billion, six hundred forty-two million, six hundred fifty-five thousand, four hundred five".