19801224 has 48 divisors (see below), whose sum is σ = 54650700. Its totient is φ = 6474624.

The previous prime is 19801217. The next prime is 19801231. The reversal of 19801224 is 42210891.

It is an interprime number because it is at equal distance from previous prime (19801217) and next prime (19801231).

It can be written as a sum of positive squares in 2 ways, for example, as 18404100 + 1397124 = 4290^2 + 1182^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1222 + ... + 6410.

Almost surely, 2^19801224 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19801224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27325350).

19801224 is an abundant number, since it is smaller than the sum of its proper divisors (34849476).

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

19801224 is a wasteful number, since it uses less digits than its factorization.

19801224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5254 (or 5247 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 19801224 is about 4449.8566269038. The cubic root of 19801224 is about 270.5394974231.

The spelling of 19801224 in words is "nineteen million, eight hundred one thousand, two hundred twenty-four".