209291872 has 24 divisors (see below), whose sum is σ = 412810776. Its totient is φ = 104451072.

The previous prime is 209291867. The next prime is 209291899. The reversal of 209291872 is 278192902.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12208 + ... + 23824.

It is an arithmetic number, because the mean of its divisors is an integer number (17200449).

Almost surely, 2^209291872 is an apocalyptic number.

It is an amenable number.

209291872 is a deficient number, since it is larger than the sum of its proper divisors (203518904).

209291872 is a wasteful number, since it uses less digits than its factorization.

209291872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12190 (or 12182 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 209291872 is about 14466.9233771386. The cubic root of 209291872 is about 593.7233385332.

It can be divided in two parts, 20929 and 1872, that added together give a square (22801 = 151²).

The spelling of 209291872 in words is "two hundred nine million, two hundred ninety-one thousand, eight hundred seventy-two".