19621442845 has 8 divisors (see below), whose sum is σ = 23547658680. Its totient is φ = 15695869440.

The previous prime is 19621442791. The next prime is 19621442849. The reversal of 19621442845 is 54824412691.

It can be written as a sum of positive squares in 4 ways, for example, as 5273954884 + 14347487961 = 72622^2 + 119781^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 19621442845 - 2²¹ = 19619345693 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 19621442795 and 19621442804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19621442849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90640 + ... + 217849.

It is an arithmetic number, because the mean of its divisors is an integer number (2943457335).

Almost surely, 2^19621442845 is an apocalyptic number.

It is an amenable number.

19621442845 is a deficient number, since it is larger than the sum of its proper divisors (3926215835).

19621442845 is a wasteful number, since it uses less digits than its factorization.

19621442845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321215.

The product of its digits is 552960, while the sum is 46.

The spelling of 19621442845 in words is "nineteen billion, six hundred twenty-one million, four hundred forty-two thousand, eight hundred forty-five".