20855537 has 2 divisors, whose sum is σ = 20855538. Its totient is φ = 20855536.

The previous prime is 20855519. The next prime is 20855563. The reversal of 20855537 is 73555802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10863616 + 9991921 = 3296^2 + 3161^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20855537 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20855497 and 20855506.

It is not a weakly prime, because it can be changed into another prime (20815537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10427768 + 10427769.

It is an arithmetic number, because the mean of its divisors is an integer number (10427769).

Almost surely, 2^20855537 is an apocalyptic number.

It is an amenable number.

20855537 is a deficient number, since it is larger than the sum of its proper divisors (1).

20855537 is an equidigital number, since it uses as much as digits as its factorization.

20855537 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 42000, while the sum is 35.

The square root of 20855537 is about 4566.7862879710. The cubic root of 20855537 is about 275.2583225568.

The spelling of 20855537 in words is "twenty million, eight hundred fifty-five thousand, five hundred thirty-seven".