19805850 has 96 divisors (see below), whose sum is σ = 57853440. Its totient is φ = 4965120.

The previous prime is 19805837. The next prime is 19805857. The reversal of 19805850 is 5850891.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19805857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 22519 + ... + 23381.

It is an arithmetic number, because the mean of its divisors is an integer number (602640).

Almost surely, 2^19805850 is an apocalyptic number.

19805850 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 19805850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28926720).

19805850 is an abundant number, since it is smaller than the sum of its proper divisors (38047590).

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

19805850 is a wasteful number, since it uses less digits than its factorization.

19805850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 901 (or 890 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 36.

The square root of 19805850 is about 4450.3763885766. The cubic root of 19805850 is about 270.5605637684.

The spelling of 19805850 in words is "nineteen million, eight hundred five thousand, eight hundred fifty".