209879072 has 54 divisors (see below), whose sum is σ = 449711703. Its totient is φ = 96375552.

The previous prime is 209879069. The next prime is 209879113. The reversal of 209879072 is 270978902.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 5 ways, for example, as 155650576 + 54228496 = 12476^2 + 7364^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=10244.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1065278 + ... + 1065474.

Almost surely, 2^209879072 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 209879072

209879072 is an abundant number, since it is smaller than the sum of its proper divisors (239832631).

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

209879072 is an equidigital number, since it uses as much as digits as its factorization.

209879072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430 (or 212 counting only the distinct ones).

The product of its (nonzero) digits is 127008, while the sum is 44.

The square root of 209879072 is about 14487.2037329500. The cubic root of 209879072 is about 594.2780802591.

Multiplying 209879072 by its product of nonzero digits (127008), we get a square (26656321176576 = 5162976²).

The spelling of 209879072 in words is "two hundred nine million, eight hundred seventy-nine thousand, seventy-two".