20700432821 has 2 divisors, whose sum is σ = 20700432822. Its totient is φ = 20700432820.

The previous prime is 20700432817. The next prime is 20700432853. The reversal of 20700432821 is 12823400702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20360436100 + 339996721 = 142690^2 + 18439^2 .

It is a cyclic number.

It is not a de Polignac number, because 20700432821 - 2² = 20700432817 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20700432521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10350216410 + 10350216411.

It is an arithmetic number, because the mean of its divisors is an integer number (10350216411).

Almost surely, 2^20700432821 is an apocalyptic number.

It is an amenable number.

20700432821 is a deficient number, since it is larger than the sum of its proper divisors (1).

20700432821 is an equidigital number, since it uses as much as digits as its factorization.

20700432821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5376, while the sum is 29.

The spelling of 20700432821 in words is "twenty billion, seven hundred million, four hundred thirty-two thousand, eight hundred twenty-one".