2105020521 has 8 divisors (see below), whose sum is σ = 3118548960. Its totient is φ = 1403346996.

The previous prime is 2105020517. The next prime is 2105020531. The reversal of 2105020521 is 1250205012.

It is not a de Polignac number, because 2105020521 - 2² = 2105020517 is a prime.

It is a super-2 number, since 2×2105020521² = 8862222787662222882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2105020494 and 2105020503.

It is not an unprimeable number, because it can be changed into a prime (2105020501) 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, 38981835 + ... + 38981888.

It is an arithmetic number, because the mean of its divisors is an integer number (389818620).

Almost surely, 2^2105020521 is an apocalyptic number.

It is an amenable number.

2105020521 is a deficient number, since it is larger than the sum of its proper divisors (1013528439).

2105020521 is an equidigital number, since it uses as much as digits as its factorization.

2105020521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77963732 (or 77963726 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 2105020521 is about 45880.5026236636. The cubic root of 2105020521 is about 1281.5988567213.

Adding to 2105020521 its reverse (1250205012), we get a palindrome (3355225533).

The spelling of 2105020521 in words is "two billion, one hundred five million, twenty thousand, five hundred twenty-one".