2105657720 has 16 divisors (see below), whose sum is σ = 4737729960. Its totient is φ = 842263072.

The previous prime is 2105657711. The next prime is 2105657731. The reversal of 2105657720 is 277565012.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26320682 + ... + 26320761.

Almost surely, 2^2105657720 is an apocalyptic number.

2105657720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2105657720 is an abundant number, since it is smaller than the sum of its proper divisors (2632072240).

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

2105657720 is a wasteful number, since it uses less digits than its factorization.

2105657720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52641454 (or 52641450 counting only the distinct ones).

The product of its (nonzero) digits is 29400, while the sum is 35.

The square root of 2105657720 is about 45887.4462135343. The cubic root of 2105657720 is about 1281.7281588850.

The spelling of 2105657720 in words is "two billion, one hundred five million, six hundred fifty-seven thousand, seven hundred twenty".