21879520340 has 12 divisors (see below), whose sum is σ = 45946992756. Its totient is φ = 8751808128.

The previous prime is 21879520331. The next prime is 21879520427. The reversal of 21879520340 is 4302597812.

It can be written as a sum of positive squares in 2 ways, for example, as 5218906564 + 16660613776 = 72242^2 + 129076^2 .

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 546987989 + ... + 546988028.

It is an arithmetic number, because the mean of its divisors is an integer number (3828916063).

Almost surely, 2^21879520340 is an apocalyptic number.

21879520340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21879520340 is an abundant number, since it is smaller than the sum of its proper divisors (24067472416).

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

21879520340 is a wasteful number, since it uses less digits than its factorization.

21879520340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1093976026 (or 1093976024 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 41.

The spelling of 21879520340 in words is "twenty-one billion, eight hundred seventy-nine million, five hundred twenty thousand, three hundred forty".