16217574721 has 4 divisors (see below), whose sum is σ = 16221870000. Its totient is φ = 16213279444.

The previous prime is 16217574713. The next prime is 16217574727. The reversal of 16217574721 is 12747571261.

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.

It is a cyclic number.

It is not a de Polignac number, because 16217574721 - 2³ = 16217574713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16217574727) 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, 2141971 + ... + 2149528.

It is an arithmetic number, because the mean of its divisors is an integer number (4055467500).

Almost surely, 2^16217574721 is an apocalyptic number.

It is an amenable number.

16217574721 is a deficient number, since it is larger than the sum of its proper divisors (4295279).

16217574721 is an equidigital number, since it uses as much as digits as its factorization.

16217574721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4295278.

The product of its digits is 164640, while the sum is 43.

The spelling of 16217574721 in words is "sixteen billion, two hundred seventeen million, five hundred seventy-four thousand, seven hundred twenty-one".