19206640728 has 384 divisors, whose sum is σ = 62052480000. Its totient is φ = 5489256960.

The previous prime is 19206640727. The next prime is 19206640729. The reversal of 19206640728 is 82704660291.

It is a happy number.

19206640728 is a `hidden beast` number, since 19 + 206 + 6 + 407 + 28 = 666.

It is an interprime number because it is at equal distance from previous prime (19206640727) and next prime (19206640729).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19206640727) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 53500213 + ... + 53500571.

It is an arithmetic number, because the mean of its divisors is an integer number (161595000).

Almost surely, 2^19206640728 is an apocalyptic number.

19206640728 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19206640728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31026240000).

19206640728 is an abundant number, since it is smaller than the sum of its proper divisors (42845839272).

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

19206640728 is a wasteful number, since it uses less digits than its factorization.

19206640728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 508 (or 487 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The spelling of 19206640728 in words is "nineteen billion, two hundred six million, six hundred forty thousand, seven hundred twenty-eight".