2120917840 has 40 divisors (see below), whose sum is σ = 5014723680. Its totient is φ = 833986176.

The previous prime is 2120917829. The next prime is 2120917847. The reversal of 2120917840 is 487190212.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 2120917796 and 2120917805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2120917847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 219954 + ... + 229393.

It is an arithmetic number, because the mean of its divisors is an integer number (125368092).

Almost surely, 2^2120917840 is an apocalyptic number.

2120917840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2120917840 is an abundant number, since it is smaller than the sum of its proper divisors (2893805840).

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

2120917840 is a wasteful number, since it uses less digits than its factorization.

2120917840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 449419 (or 449413 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 2120917840 is about 46053.4237598031. The cubic root of 2120917840 is about 1284.8170218952.

The spelling of 2120917840 in words is "two billion, one hundred twenty million, nine hundred seventeen thousand, eight hundred forty".