19840694449 has 9 divisors (see below), whose sum is σ = 20106298233. Its totient is φ = 19578559572.

The previous prime is 19840694411. The next prime is 19840694479. The reversal of 19840694449 is 94449604891.

The square root of 19840694449 is 140857.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 19840694449 - 2⁹ = 19840693937 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19840694393 and 19840694402.

It is not an unprimeable number, because it can be changed into a prime (19840694479) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 11126812 + ... + 11128594.

It is an arithmetic number, because the mean of its divisors is an integer number (2234033137).

Almost surely, 2^19840694449 is an apocalyptic number.

19840694449 is the 140857-th square number.

19840694449 is the 70429-th centered octagonal number.

It is an amenable number.

19840694449 is a deficient number, since it is larger than the sum of its proper divisors (265603784).

19840694449 is an frugal number, since it uses more digits than its factorization.

19840694449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3724 (or 1862 counting only the distinct ones).

The product of its (nonzero) digits is 8957952, while the sum is 58.

The spelling of 19840694449 in words is "nineteen billion, eight hundred forty million, six hundred ninety-four thousand, four hundred forty-nine".