19964420787 has 30 divisors (see below), whose sum is σ = 27857069148. Its totient is φ = 12718180608.

The previous prime is 19964420771. The next prime is 19964420797. The reversal of 19964420787 is 78702446991.

It is a happy number.

It is not a de Polignac number, because 19964420787 - 2⁴ = 19964420771 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19964420737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 205818723 + ... + 205818819.

Almost surely, 2^19964420787 is an apocalyptic number.

19964420787 is a deficient number, since it is larger than the sum of its proper divisors (7892648361).

19964420787 is an frugal number, since it uses more digits than its factorization.

19964420787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313 (or 129 counting only the distinct ones).

The product of its (nonzero) digits is 6096384, while the sum is 57.

The spelling of 19964420787 in words is "nineteen billion, nine hundred sixty-four million, four hundred twenty thousand, seven hundred eighty-seven".