20805377 has 2 divisors, whose sum is σ = 20805378. Its totient is φ = 20805376.

The previous prime is 20805373. The next prime is 20805397. The reversal of 20805377 is 77350802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20214016 + 591361 = 4496^2 + 769^2 .

It is a cyclic number.

It is not a de Polignac number, because 20805377 - 2² = 20805373 is a prime.

It is a super-2 number, since 2×20805377² = 865727424224258, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20805373) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10402688 + 10402689.

It is an arithmetic number, because the mean of its divisors is an integer number (10402689).

Almost surely, 2^20805377 is an apocalyptic number.

It is an amenable number.

20805377 is a deficient number, since it is larger than the sum of its proper divisors (1).

20805377 is an equidigital number, since it uses as much as digits as its factorization.

20805377 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11760, while the sum is 32.

The square root of 20805377 is about 4561.2911549253. The cubic root of 20805377 is about 275.0374692747.

The spelling of 20805377 in words is "twenty million, eight hundred five thousand, three hundred seventy-seven".