21286929408 has 44 divisors (see below), whose sum is σ = 56737435920. Its totient is φ = 7095642112.

The previous prime is 21286929401. The next prime is 21286929409. The reversal of 21286929408 is 80492968212.

It is not an unprimeable number, because it can be changed into a prime (21286929401) 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 in 3 ways as a sum of consecutive naturals, for example, 3461598 + ... + 3467741.

It is an arithmetic number, because the mean of its divisors is an integer number (1289487180).

Almost surely, 2^21286929408 is an apocalyptic number.

It is an amenable number.

21286929408 is an abundant number, since it is smaller than the sum of its proper divisors (35450506512).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21286929408 is an equidigital number, since it uses as much as digits as its factorization.

21286929408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6929362 (or 6929344 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 51.

The spelling of 21286929408 in words is "twenty-one billion, two hundred eighty-six million, nine hundred twenty-nine thousand, four hundred eight".