209525792081 has 16 divisors (see below), whose sum is σ = 231606998784. Its totient is φ = 188536786944.

The previous prime is 209525792059. The next prime is 209525792117. The reversal of 209525792081 is 180297525902.

It is a happy number.

209525792081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-209525792081 is a prime.

It is a super-2 number, since 2×209525792081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (209525792381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 699380 + ... + 952986.

It is an arithmetic number, because the mean of its divisors is an integer number (14475437424).

Almost surely, 2^209525792081 is an apocalyptic number.

It is an amenable number.

209525792081 is a deficient number, since it is larger than the sum of its proper divisors (22081206703).

209525792081 is a wasteful number, since it uses less digits than its factorization.

209525792081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255760.

The product of its (nonzero) digits is 907200, while the sum is 50.

The spelling of 209525792081 in words is "two hundred nine billion, five hundred twenty-five million, seven hundred ninety-two thousand, eighty-one".