16531720958209 has 8 divisors (see below), whose sum is σ = 16662221419520. Its totient is φ = 16401225644496.

The previous prime is 16531720958191. The next prime is 16531720958237. The reversal of 16531720958209 is 90285902713561.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 16531720958209 - 2²³ = 16531712569601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16531720958299) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5293822 + ... + 7815880.

It is an arithmetic number, because the mean of its divisors is an integer number (2082777677440).

Almost surely, 2^{16531720958209} is an apocalyptic number.

It is an amenable number.

16531720958209 is a deficient number, since it is larger than the sum of its proper divisors (130500461311).

16531720958209 is a wasteful number, since it uses less digits than its factorization.

16531720958209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2573799.

The product of its (nonzero) digits is 8164800, while the sum is 58.

The spelling of 16531720958209 in words is "sixteen trillion, five hundred thirty-one billion, seven hundred twenty million, nine hundred fifty-eight thousand, two hundred nine".