21078308082 has 64 divisors (see below), whose sum is σ = 47031054336. Its totient is φ = 6254038080.

The previous prime is 21078308029. The next prime is 21078308093. The reversal of 21078308082 is 28080387012.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 21078308082.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 668893 + ... + 699695.

It is an arithmetic number, because the mean of its divisors is an integer number (734860224).

Almost surely, 2^21078308082 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21078308082, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23515527168).

21078308082 is an abundant number, since it is smaller than the sum of its proper divisors (25952746254).

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

21078308082 is a wasteful number, since it uses less digits than its factorization.

21078308082 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31135.

The product of its (nonzero) digits is 43008, while the sum is 39.

The spelling of 21078308082 in words is "twenty-one billion, seventy-eight million, three hundred eight thousand, eighty-two".