20292821 has 2 divisors, whose sum is σ = 20292822. Its totient is φ = 20292820.

The previous prime is 20292793. The next prime is 20292841. The reversal of 20292821 is 12829202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14938225 + 5354596 = 3865^2 + 2314^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20292821 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20292841) 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, 10146410 + 10146411.

It is an arithmetic number, because the mean of its divisors is an integer number (10146411).

Almost surely, 2^20292821 is an apocalyptic number.

It is an amenable number.

20292821 is a deficient number, since it is larger than the sum of its proper divisors (1).

20292821 is an equidigital number, since it uses as much as digits as its factorization.

20292821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 20292821 is about 4504.7553762663. The cubic root of 20292821 is about 272.7600793902.

The spelling of 20292821 in words is "twenty million, two hundred ninety-two thousand, eight hundred twenty-one".