19808927550 has 108 divisors (see below), whose sum is σ = 54246543624. Its totient is φ = 5182382400.

The previous prime is 19808927513. The next prime is 19808927563. The reversal of 19808927550 is 5572980891.

19808927550 is a `hidden beast` number, since 1 + 9 + 8 + 0 + 89 + 2 + 7 + 550 = 666.

It is a super-2 number, since 2×19808927550² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 1256215 + ... + 1271885.

Almost surely, 2^19808927550 is an apocalyptic number.

19808927550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 19808927550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27123271812).

19808927550 is an abundant number, since it is smaller than the sum of its proper divisors (34437616074).

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

19808927550 is a wasteful number, since it uses less digits than its factorization.

19808927550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15795 (or 15734 counting only the distinct ones).

The product of its (nonzero) digits is 1814400, while the sum is 54.

The spelling of 19808927550 in words is "nineteen billion, eight hundred eight million, nine hundred twenty-seven thousand, five hundred fifty".