16681008731 has 4 divisors (see below), whose sum is σ = 16681761264. Its totient is φ = 16680256200.

The previous prime is 16681008709. The next prime is 16681008733. The reversal of 16681008731 is 13780018661.

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 16681008731 - 2⁶ = 16681008667 is a prime.

It is a super-2 number, since 2×16681008731² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16681008733) 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, 341975 + ... + 387696.

It is an arithmetic number, because the mean of its divisors is an integer number (4170440316).

Almost surely, 2^16681008731 is an apocalyptic number.

16681008731 is a deficient number, since it is larger than the sum of its proper divisors (752533).

16681008731 is an equidigital number, since it uses as much as digits as its factorization.

16681008731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 752532.

The product of its (nonzero) digits is 48384, while the sum is 41.

The spelling of 16681008731 in words is "sixteen billion, six hundred eighty-one million, eight thousand, seven hundred thirty-one".