21909139779411 has 24 divisors (see below), whose sum is σ = 34760496376320. Its totient is φ = 13235727461616.

The previous prime is 21909139779403. The next prime is 21909139779419. The reversal of 21909139779411 is 11497793190912.

21909139779411 is a `hidden beast` number, since 2 + 1 + 90 + 91 + 397 + 79 + 4 + 1 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (21909139779403) and next prime (21909139779419).

It is not a de Polignac number, because 21909139779411 - 2³ = 21909139779403 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21909139779419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2785292251 + ... + 2785300116.

It is an arithmetic number, because the mean of its divisors is an integer number (1448354015680).

Almost surely, 2^{21909139779411} is an apocalyptic number.

21909139779411 is a deficient number, since it is larger than the sum of its proper divisors (12851356596909).

21909139779411 is a wasteful number, since it uses less digits than its factorization.

21909139779411 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5570592415 (or 5570592412 counting only the distinct ones).

The product of its (nonzero) digits is 7715736, while the sum is 63.

The spelling of 21909139779411 in words is "twenty-one trillion, nine hundred nine billion, one hundred thirty-nine million, seven hundred seventy-nine thousand, four hundred eleven".