19720224 has 36 divisors (see below), whose sum is σ = 56080206. Its totient is φ = 6573312.

The previous prime is 19720193. The next prime is 19720231. The reversal of 19720224 is 42202791.

It can be written as a sum of positive squares in only one way, i.e., 19184400 + 535824 = 4380^2 + 732^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×19720224² = 777774469220352, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 33949 + ... + 34524.

Almost surely, 2^19720224 is an apocalyptic number.

It is an amenable number.

19720224 is an abundant number, since it is smaller than the sum of its proper divisors (36359982).

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

19720224 is a wasteful number, since it uses less digits than its factorization.

19720224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68489 (or 68478 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 19720224 is about 4440.7458832948. The cubic root of 19720224 is about 270.1700985776.

The spelling of 19720224 in words is "nineteen million, seven hundred twenty thousand, two hundred twenty-four".