20821846319 has 2 divisors, whose sum is σ = 20821846320. Its totient is φ = 20821846318.

The previous prime is 20821846307. The next prime is 20821846321. The reversal of 20821846319 is 91364812802.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20821846319 - 2²⁸ = 20553410863 is a prime.

It is a super-2 number, since 2×20821846319² (a number of 21 digits) contains 22 as substring.

Together with 20821846321, it forms a pair of twin primes.

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 20821846319.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20821846349) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10410923159 + 10410923160.

It is an arithmetic number, because the mean of its divisors is an integer number (10410923160).

Almost surely, 2^20821846319 is an apocalyptic number.

20821846319 is a deficient number, since it is larger than the sum of its proper divisors (1).

20821846319 is an equidigital number, since it uses as much as digits as its factorization.

20821846319 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 165888, while the sum is 44.

The spelling of 20821846319 in words is "twenty billion, eight hundred twenty-one million, eight hundred forty-six thousand, three hundred nineteen".