20995837 has 2 divisors, whose sum is σ = 20995838. Its totient is φ = 20995836.

The previous prime is 20995831. The next prime is 20995859. The reversal of 20995837 is 73859902.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11329956 + 9665881 = 3366^2 + 3109^2 .

It is a cyclic number.

It is not a de Polignac number, because 20995837 - 2¹⁵ = 20963069 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20995793 and 20995802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20995831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10497918 + 10497919.

It is an arithmetic number, because the mean of its divisors is an integer number (10497919).

Almost surely, 2^20995837 is an apocalyptic number.

It is an amenable number.

20995837 is a deficient number, since it is larger than the sum of its proper divisors (1).

20995837 is an equidigital number, since it uses as much as digits as its factorization.

20995837 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 136080, while the sum is 43.

The square root of 20995837 is about 4582.1214519041. The cubic root of 20995837 is about 275.8741856375.

The spelling of 20995837 in words is "twenty million, nine hundred ninety-five thousand, eight hundred thirty-seven".