16191207649 has 4 divisors (see below), whose sum is σ = 16193981700. Its totient is φ = 16188433600.

The previous prime is 16191207631. The next prime is 16191207661. The reversal of 16191207649 is 94670219161.

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 4062150225 + 12129057424 = 63735^2 + 110132^2 .

It is a cyclic number.

It is not a de Polignac number, because 16191207649 - 2¹³ = 16191199457 is a prime.

It is a super-2 number, since 2×16191207649² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16191207599 and 16191207608.

It is not an unprimeable number, because it can be changed into a prime (16191207689) 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, 1378252 + ... + 1389949.

It is an arithmetic number, because the mean of its divisors is an integer number (4048495425).

Almost surely, 2^16191207649 is an apocalyptic number.

It is an amenable number.

16191207649 is a deficient number, since it is larger than the sum of its proper divisors (2774051).

16191207649 is an equidigital number, since it uses as much as digits as its factorization.

16191207649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2774050.

The product of its (nonzero) digits is 163296, while the sum is 46.

The spelling of 16191207649 in words is "sixteen billion, one hundred ninety-one million, two hundred seven thousand, six hundred forty-nine".