209872716 has 12 divisors (see below), whose sum is σ = 489703032. Its totient is φ = 69957568.

The previous prime is 209872711. The next prime is 209872717. The reversal of 209872716 is 617278902.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (209872711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8744685 + ... + 8744708.

It is an arithmetic number, because the mean of its divisors is an integer number (40808586).

Almost surely, 2^209872716 is an apocalyptic number.

It is an amenable number.

209872716 is an abundant number, since it is smaller than the sum of its proper divisors (279830316).

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

209872716 is a wasteful number, since it uses less digits than its factorization.

209872716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17489400 (or 17489398 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 42.

The square root of 209872716 is about 14486.9843652846. The cubic root of 209872716 is about 594.2720811385.

The spelling of 209872716 in words is "two hundred nine million, eight hundred seventy-two thousand, seven hundred sixteen".