19211068816 has 15 divisors (see below), whose sum is σ = 37222520043. Its totient is φ = 9605257200.

The previous prime is 19211068813. The next prime is 19211068817. The reversal of 19211068816 is 61886011291.

The square root of 19211068816 is 138604.

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

It is a super-3 number, since 3×19211068816³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19211068813) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 537091 + ... + 571741.

Almost surely, 2^19211068816 is an apocalyptic number.

19211068816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

19211068816 is the 138604-th square number.

It is an amenable number.

19211068816 is a deficient number, since it is larger than the sum of its proper divisors (18011451227).

19211068816 is an frugal number, since it uses more digits than its factorization.

19211068816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69310 (or 34653 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 43.

The spelling of 19211068816 in words is "nineteen billion, two hundred eleven million, sixty-eight thousand, eight hundred sixteen".