19870807816 has 16 divisors (see below), whose sum is σ = 39449398140. Its totient is φ = 9350968320.

The previous prime is 19870807811. The next prime is 19870807819. The reversal of 19870807816 is 61870807891.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 17840944900 + 2029862916 = 133570^2 + 45054^2 .

It is not an unprimeable number, because it can be changed into a prime (19870807811) 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, 73054305 + ... + 73054576.

Almost surely, 2^19870807816 is an apocalyptic number.

It is an amenable number.

19870807816 is a deficient number, since it is larger than the sum of its proper divisors (19578590324).

19870807816 is a wasteful number, since it uses less digits than its factorization.

19870807816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146108904 (or 146108900 counting only the distinct ones).

The product of its (nonzero) digits is 1354752, while the sum is 55.

The spelling of 19870807816 in words is "nineteen billion, eight hundred seventy million, eight hundred seven thousand, eight hundred sixteen".