2109505657840 has 160 divisors (see below), whose sum is σ = 5638946512896. Its totient is φ = 718918072320.

The previous prime is 2109505657837. The next prime is 2109505657871. The reversal of 2109505657840 is 487565059012.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 153266799 + ... + 153280561.

Almost surely, 2^{2109505657840} is an apocalyptic number.

2109505657840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2109505657840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2819473256448).

2109505657840 is an abundant number, since it is smaller than the sum of its proper divisors (3529440855056).

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

2109505657840 is a wasteful number, since it uses less digits than its factorization.

2109505657840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15407 (or 15401 counting only the distinct ones).

The product of its (nonzero) digits is 3024000, while the sum is 52.

The spelling of 2109505657840 in words is "two trillion, one hundred nine billion, five hundred five million, six hundred fifty-seven thousand, eight hundred forty".