209912004 has 36 divisors (see below), whose sum is σ = 531108396. Its totient is φ = 69905088.

The previous prime is 209911991. The next prime is 209912009. The reversal of 209912004 is 400219902.

It can be written as a sum of positive squares in 2 ways, for example, as 193265604 + 16646400 = 13902^2 + 4080^2 .

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

It is a super-3 number, since 3×209912004³ (a number of 26 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (209912009) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 50302 + ... + 54314.

It is an arithmetic number, because the mean of its divisors is an integer number (14753011).

Almost surely, 2^209912004 is an apocalyptic number.

It is an amenable number.

209912004 is an abundant number, since it is smaller than the sum of its proper divisors (321196392).

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

209912004 is a wasteful number, since it uses less digits than its factorization.

209912004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5476 (or 5471 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 209912004 is about 14488.3402776163. The cubic root of 209912004 is about 594.3091612399.

The spelling of 209912004 in words is "two hundred nine million, nine hundred twelve thousand, four".