19729117338 has 96 divisors (see below), whose sum is σ = 48924463104. Its totient is φ = 5192279808.

The previous prime is 19729117337. The next prime is 19729117391. The reversal of 19729117338 is 83371192791.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (19729117337) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 553195 + ... + 587777.

It is an arithmetic number, because the mean of its divisors is an integer number (509629824).

Almost surely, 2^19729117338 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19729117338, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24462231552).

19729117338 is an abundant number, since it is smaller than the sum of its proper divisors (29195345766).

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

19729117338 is a wasteful number, since it uses less digits than its factorization.

19729117338 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34676 (or 34659 counting only the distinct ones).

The product of its digits is 571536, while the sum is 51.

The spelling of 19729117338 in words is "nineteen billion, seven hundred twenty-nine million, one hundred seventeen thousand, three hundred thirty-eight".