19773840840 has 128 divisors (see below), whose sum is σ = 63942600960. Its totient is φ = 4862997504.

The previous prime is 19773840833. The next prime is 19773840859. The reversal of 19773840840 is 4804837791.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1924597 + ... + 1934843.

It is an arithmetic number, because the mean of its divisors is an integer number (499551570).

Almost surely, 2^19773840840 is an apocalyptic number.

19773840840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19773840840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31971300480).

19773840840 is an abundant number, since it is smaller than the sum of its proper divisors (44168760120).

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

19773840840 is a wasteful number, since it uses less digits than its factorization.

19773840840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11511 (or 11507 counting only the distinct ones).

The product of its (nonzero) digits is 1354752, while the sum is 51.

The spelling of 19773840840 in words is "nineteen billion, seven hundred seventy-three million, eight hundred forty thousand, eight hundred forty".