19661948225 has 12 divisors (see below), whose sum is σ = 24451088304. Its totient is φ = 15684221520.

The previous prime is 19661948221. The next prime is 19661948227. The reversal of 19661948225 is 52284916691.

It is not a de Polignac number, because 19661948225 - 2² = 19661948221 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19661948221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1124579 + ... + 1141928.

It is an arithmetic number, because the mean of its divisors is an integer number (2037590692).

Almost surely, 2^19661948225 is an apocalyptic number.

It is an amenable number.

19661948225 is a deficient number, since it is larger than the sum of its proper divisors (4789140079).

19661948225 is a wasteful number, since it uses less digits than its factorization.

19661948225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2266864 (or 2266859 counting only the distinct ones).

The product of its digits is 1866240, while the sum is 53.

The spelling of 19661948225 in words is "nineteen billion, six hundred sixty-one million, nine hundred forty-eight thousand, two hundred twenty-five".