21459943380 has 48 divisors (see below), whose sum is σ = 61366314240. Its totient is φ = 5600892288.

The previous prime is 21459943367. The next prime is 21459943397. The reversal of 21459943380 is 8334995412.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3802135 + ... + 3807774.

It is an arithmetic number, because the mean of its divisors is an integer number (1278464880).

Almost surely, 2^21459943380 is an apocalyptic number.

21459943380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21459943380 is an abundant number, since it is smaller than the sum of its proper divisors (39906370860).

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

21459943380 is a wasteful number, since it uses less digits than its factorization.

21459943380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7609968 (or 7609966 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 48.

The spelling of 21459943380 in words is "twenty-one billion, four hundred fifty-nine million, nine hundred forty-three thousand, three hundred eighty".