20999379843 has 48 divisors (see below), whose sum is σ = 33960457440. Its totient is φ = 12890306304.

The previous prime is 20999379833. The next prime is 20999379857. The reversal of 20999379843 is 34897399902.

It is not a de Polignac number, because 20999379843 - 2¹³ = 20999371651 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20999379833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1283905 + ... + 1300157.

It is an arithmetic number, because the mean of its divisors is an integer number (707509530).

Almost surely, 2^20999379843 is an apocalyptic number.

20999379843 is a deficient number, since it is larger than the sum of its proper divisors (12961077597).

20999379843 is a wasteful number, since it uses less digits than its factorization.

20999379843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16690 (or 16678 counting only the distinct ones).

The product of its (nonzero) digits is 26453952, while the sum is 63.

The spelling of 20999379843 in words is "twenty billion, nine hundred ninety-nine million, three hundred seventy-nine thousand, eight hundred forty-three".