2101957987 has 2 divisors, whose sum is σ = 2101957988. Its totient is φ = 2101957986.

The previous prime is 2101957939. The next prime is 2101957993. The reversal of 2101957987 is 7897591012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2101957987 is a prime.

It is a super-2 number, since 2×2101957987² = 8836454758226184338, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2101957987.

It is not a weakly prime, because it can be changed into another prime (2101157987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050978993 + 1050978994.

It is an arithmetic number, because the mean of its divisors is an integer number (1050978994).

Almost surely, 2^2101957987 is an apocalyptic number.

2101957987 is a deficient number, since it is larger than the sum of its proper divisors (1).

2101957987 is an equidigital number, since it uses as much as digits as its factorization.

2101957987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 317520, while the sum is 49.

The square root of 2101957987 is about 45847.1153618197. The cubic root of 2101957987 is about 1280.9770345899.

The spelling of 2101957987 in words is "two billion, one hundred one million, nine hundred fifty-seven thousand, nine hundred eighty-seven".