19688609778 has 32 divisors (see below), whose sum is σ = 40778470656. Its totient is φ = 6333006288.

The previous prime is 19688609767. The next prime is 19688609783. The reversal of 19688609778 is 87790688691.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 438300 + ... + 481127.

It is an arithmetic number, because the mean of its divisors is an integer number (1274327208).

Almost surely, 2^19688609778 is an apocalyptic number.

19688609778 is an abundant number, since it is smaller than the sum of its proper divisors (21089860878).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19688609778 is a wasteful number, since it uses less digits than its factorization.

19688609778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 919558.

The product of its (nonzero) digits is 73156608, while the sum is 69.

The spelling of 19688609778 in words is "nineteen billion, six hundred eighty-eight million, six hundred nine thousand, seven hundred seventy-eight".