19649433641 has 4 divisors (see below), whose sum is σ = 19751244372. Its totient is φ = 19547622912.

The previous prime is 19649433611. The next prime is 19649433649. The reversal of 19649433641 is 14633494691.

It is a happy number.

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 2323240000 + 17326193641 = 48200^2 + 131629^2 .

It is a cyclic number.

It is not a de Polignac number, because 19649433641 - 2¹⁴ = 19649417257 is a prime.

It is a super-2 number, since 2×19649433641² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19649433641.

It is not an unprimeable number, because it can be changed into a prime (19649433649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50905076 + ... + 50905461.

It is an arithmetic number, because the mean of its divisors is an integer number (4937811093).

Almost surely, 2^19649433641 is an apocalyptic number.

It is an amenable number.

19649433641 is a deficient number, since it is larger than the sum of its proper divisors (101810731).

19649433641 is a wasteful number, since it uses less digits than its factorization.

19649433641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101810730.

The product of its digits is 1679616, while the sum is 50.

The spelling of 19649433641 in words is "nineteen billion, six hundred forty-nine million, four hundred thirty-three thousand, six hundred forty-one".