19440509946 has 128 divisors (see below), whose sum is σ = 48187560960. Its totient is φ = 5140454400.

The previous prime is 19440509941. The next prime is 19440509947. The reversal of 19440509946 is 64990504491.

It is not an unprimeable number, because it can be changed into a prime (19440509941) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 9666081 + ... + 9668091.

It is an arithmetic number, because the mean of its divisors is an integer number (376465320).

Almost surely, 2^19440509946 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19440509946, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24093780480).

19440509946 is an abundant number, since it is smaller than the sum of its proper divisors (28747051014).

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

19440509946 is a wasteful number, since it uses less digits than its factorization.

19440509946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2652.

The product of its (nonzero) digits is 1399680, while the sum is 51.

The spelling of 19440509946 in words is "nineteen billion, four hundred forty million, five hundred nine thousand, nine hundred forty-six".