19191778412 has 24 divisors (see below), whose sum is σ = 33687439632. Its totient is φ = 9566827200.

The previous prime is 19191778409. The next prime is 19191778421. The reversal of 19191778412 is 21487719191.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3602783 + ... + 3608105.

It is an arithmetic number, because the mean of its divisors is an integer number (1403643318).

Almost surely, 2^19191778412 is an apocalyptic number.

It is an amenable number.

19191778412 is a deficient number, since it is larger than the sum of its proper divisors (14495661220).

19191778412 is a wasteful number, since it uses less digits than its factorization.

19191778412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7889 (or 7887 counting only the distinct ones).

The product of its digits is 254016, while the sum is 50.

The spelling of 19191778412 in words is "nineteen billion, one hundred ninety-one million, seven hundred seventy-eight thousand, four hundred twelve".