20755121 has 2 divisors, whose sum is σ = 20755122. Its totient is φ = 20755120.

The previous prime is 20755109. The next prime is 20755129. The reversal of 20755121 is 12155702.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18318400 + 2436721 = 4280^2 + 1561^2 .

It is a cyclic number.

It is not a de Polignac number, because 20755121 - 2⁶ = 20755057 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20755129) 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, 10377560 + 10377561.

It is an arithmetic number, because the mean of its divisors is an integer number (10377561).

Almost surely, 2^20755121 is an apocalyptic number.

It is an amenable number.

20755121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20755121 is an equidigital number, since it uses as much as digits as its factorization.

20755121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 700, while the sum is 23.

The square root of 20755121 is about 4555.7788576708. The cubic root of 20755121 is about 274.8158370272.

The spelling of 20755121 in words is "twenty million, seven hundred fifty-five thousand, one hundred twenty-one".