19746064778 has 12 divisors (see below), whose sum is σ = 32556528690. Its totient is φ = 8975483880.

The previous prime is 19746064777. The next prime is 19746064829. The reversal of 19746064778 is 87746064791.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 17374666969 + 2371397809 = 131813^2 + 48697^2 .

It is not an unprimeable number, because it can be changed into a prime (19746064777) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 40797413 + ... + 40797896.

Almost surely, 2^19746064778 is an apocalyptic number.

19746064778 is a deficient number, since it is larger than the sum of its proper divisors (12810463912).

19746064778 is a wasteful number, since it uses less digits than its factorization.

19746064778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81595333 (or 81595322 counting only the distinct ones).

The product of its (nonzero) digits is 14224896, while the sum is 59.

The spelling of 19746064778 in words is "nineteen billion, seven hundred forty-six million, sixty-four thousand, seven hundred seventy-eight".