20752021 has 2 divisors, whose sum is σ = 20752022. Its totient is φ = 20752020.

The previous prime is 20752013. The next prime is 20752031. The reversal of 20752021 is 12025702.

20752021 = T₃₇₁₈ + T₃₇₁₉ + T₃₇₂₀.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15689521 + 5062500 = 3961^2 + 2250^2 .

It is a cyclic number.

It is not a de Polignac number, because 20752021 - 2³ = 20752013 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20752021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20752001) 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, 10376010 + 10376011.

It is an arithmetic number, because the mean of its divisors is an integer number (10376011).

Almost surely, 2^20752021 is an apocalyptic number.

20752021 is the 3720-th centered triangular number.

It is an amenable number.

20752021 is a deficient number, since it is larger than the sum of its proper divisors (1).

20752021 is an equidigital number, since it uses as much as digits as its factorization.

20752021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 20752021 is about 4555.4386177403. The cubic root of 20752021 is about 274.8021541147.

Adding to 20752021 its reverse (12025702), we get a palindrome (32777723).

It can be divided in two parts, 2075 and 2021, that added together give a 12-th power (4096 = 2¹²).

The spelling of 20752021 in words is "twenty million, seven hundred fifty-two thousand, twenty-one".