19809850 has 12 divisors (see below), whose sum is σ = 36846414. Its totient is φ = 7923920.

The previous prime is 19809833. The next prime is 19809851. The reversal of 19809850 is 5890891.

It can be written as a sum of positive squares in 3 ways, for example, as 8767521 + 11042329 = 2961^2 + 3323^2 .

It is not an unprimeable number, because it can be changed into a prime (19809851) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 198049 + ... + 198148.

Almost surely, 2^19809850 is an apocalyptic number.

19809850 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19809850 is a deficient number, since it is larger than the sum of its proper divisors (17036564).

19809850 is a wasteful number, since it uses less digits than its factorization.

19809850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396209 (or 396204 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 40.

The square root of 19809850 is about 4450.8257660798. The cubic root of 19809850 is about 270.5787767275.

The spelling of 19809850 in words is "nineteen million, eight hundred nine thousand, eight hundred fifty".