16677012721 has 4 divisors (see below), whose sum is σ = 16683583600. Its totient is φ = 16670441844.

The previous prime is 16677012691. The next prime is 16677012749. The reversal of 16677012721 is 12721077661.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12721077661 = 27739 ⋅458599.

It is a cyclic number.

It is not a de Polignac number, because 16677012721 - 2¹³ = 16677004529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16677012791) 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, 3281631 + ... + 3286708.

It is an arithmetic number, because the mean of its divisors is an integer number (4170895900).

Almost surely, 2^16677012721 is an apocalyptic number.

It is an amenable number.

16677012721 is a deficient number, since it is larger than the sum of its proper divisors (6570879).

16677012721 is an equidigital number, since it uses as much as digits as its factorization.

16677012721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6570878.

The product of its (nonzero) digits is 49392, while the sum is 40.

The spelling of 16677012721 in words is "sixteen billion, six hundred seventy-seven million, twelve thousand, seven hundred twenty-one".