21078346408 has 16 divisors (see below), whose sum is σ = 45167885280. Its totient is φ = 9033577008.

The previous prime is 21078346357. The next prime is 21078346409. The reversal of 21078346408 is 80464387012.

It is not an unprimeable number, because it can be changed into a prime (21078346409) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 188199466 + ... + 188199577.

It is an arithmetic number, because the mean of its divisors is an integer number (2822992830).

Almost surely, 2^21078346408 is an apocalyptic number.

21078346408 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21078346408 is an abundant number, since it is smaller than the sum of its proper divisors (24089538872).

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

21078346408 is a wasteful number, since it uses less digits than its factorization.

21078346408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376399056 (or 376399052 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 43.

The spelling of 21078346408 in words is "twenty-one billion, seventy-eight million, three hundred forty-six thousand, four hundred eight".