19561938496 has 21 divisors (see below), whose sum is σ = 38820442171. Its totient is φ = 9780409792.

The previous prime is 19561938481. The next prime is 19561938503. The reversal of 19561938496 is 69483916591.

The square root of 19561938496 is 139864.

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

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1110171 + ... + 1127653.

Almost surely, 2^19561938496 is an apocalyptic number.

19561938496 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

19561938496 is the 139864-th square number.

It is an amenable number.

19561938496 is a deficient number, since it is larger than the sum of its proper divisors (19258503675).

19561938496 is an frugal number, since it uses more digits than its factorization.

19561938496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34978 (or 17485 counting only the distinct ones).

The product of its digits is 12597120, while the sum is 61.

The spelling of 19561938496 in words is "nineteen billion, five hundred sixty-one million, nine hundred thirty-eight thousand, four hundred ninety-six".