209911952512 has 16 divisors (see below), whose sum is σ = 418183968150. Its totient is φ = 104955976192.

The previous prime is 209911952431. The next prime is 209911952533. The reversal of 209911952512 is 215259119902.

It can be written as a sum of positive squares in only one way, i.e., 197612255296 + 12299697216 = 444536^2 + 110904^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a super-2 number, since 2×209911952512² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 819968437 + ... + 819968692.

Almost surely, 2^209911952512 is an apocalyptic number.

It is an amenable number.

209911952512 is a deficient number, since it is larger than the sum of its proper divisors (208272015638).

209911952512 is an equidigital number, since it uses as much as digits as its factorization.

209911952512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1639937143 (or 1639937131 counting only the distinct ones).

The product of its (nonzero) digits is 145800, while the sum is 46.

The spelling of 209911952512 in words is "two hundred nine billion, nine hundred eleven million, nine hundred fifty-two thousand, five hundred twelve".