20786761 has 2 divisors, whose sum is σ = 20786762. Its totient is φ = 20786760.

The previous prime is 20786749. The next prime is 20786797. The reversal of 20786761 is 16768702.

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., 18113536 + 2673225 = 4256^2 + 1635^2 .

It is a cyclic number.

It is not a de Polignac number, because 20786761 - 2⁵ = 20786729 is a prime.

It is a super-2 number, since 2×20786761² = 864178865742242, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20786761.

It is not a weakly prime, because it can be changed into another prime (20786561) 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, 10393380 + 10393381.

It is an arithmetic number, because the mean of its divisors is an integer number (10393381).

Almost surely, 2^20786761 is an apocalyptic number.

It is an amenable number.

20786761 is a deficient number, since it is larger than the sum of its proper divisors (1).

20786761 is an equidigital number, since it uses as much as digits as its factorization.

20786761 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28224, while the sum is 37.

The square root of 20786761 is about 4559.2500479794. The cubic root of 20786761 is about 274.9554131570.

It can be divided in two parts, 207 and 86761, that added together give a palindrome (86968).

The spelling of 20786761 in words is "twenty million, seven hundred eighty-six thousand, seven hundred sixty-one".