16205902609 has 4 divisors (see below), whose sum is σ = 17452510516. Its totient is φ = 14959294704.

The previous prime is 16205902567. The next prime is 16205902621. The reversal of 16205902609 is 90620950261.

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 3934801984 + 12271100625 = 62728^2 + 110775^2 .

It is a cyclic number.

It is not a de Polignac number, because 16205902609 - 2⁷ = 16205902481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16205905609) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 623303934 + ... + 623303959.

It is an arithmetic number, because the mean of its divisors is an integer number (4363127629).

Almost surely, 2^16205902609 is an apocalyptic number.

It is an amenable number.

16205902609 is a deficient number, since it is larger than the sum of its proper divisors (1246607907).

16205902609 is a wasteful number, since it uses less digits than its factorization.

16205902609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1246607906.

The product of its (nonzero) digits is 58320, while the sum is 40.

The spelling of 16205902609 in words is "sixteen billion, two hundred five million, nine hundred two thousand, six hundred nine".