209915081456 has 40 divisors (see below), whose sum is σ = 449357873184. Its totient is φ = 94488627200.

The previous prime is 209915081449. The next prime is 209915081459. The reversal of 209915081456 is 654180519902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209915081459) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16770845 + ... + 16783356.

Almost surely, 2^209915081456 is an apocalyptic number.

It is an amenable number.

209915081456 is an abundant number, since it is smaller than the sum of its proper divisors (239442791728).

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

209915081456 is a wasteful number, since it uses less digits than its factorization.

209915081456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33554249 (or 33554243 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 50.

The spelling of 209915081456 in words is "two hundred nine billion, nine hundred fifteen million, eighty-one thousand, four hundred fifty-six".