19938888947 has 4 divisors (see below), whose sum is σ = 20003836776. Its totient is φ = 19873941120.

The previous prime is 19938888943. The next prime is 19938888953. The reversal of 19938888947 is 74988883991.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 19938888947 - 2² = 19938888943 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19938888943) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32473454 + ... + 32474067.

It is an arithmetic number, because the mean of its divisors is an integer number (5000959194).

Almost surely, 2^19938888947 is an apocalyptic number.

19938888947 is a deficient number, since it is larger than the sum of its proper divisors (64947829).

19938888947 is an equidigital number, since it uses as much as digits as its factorization.

19938888947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64947828.

The product of its digits is 250822656, while the sum is 74.

The spelling of 19938888947 in words is "nineteen billion, nine hundred thirty-eight million, eight hundred eighty-eight thousand, nine hundred forty-seven".