21409835280 has 40 divisors (see below), whose sum is σ = 66370490112. Its totient is φ = 5709289344.

The previous prime is 21409835273. The next prime is 21409835281. The reversal of 21409835280 is 8253890412.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (21409835281) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44603584 + ... + 44604063.

Almost surely, 2^21409835280 is an apocalyptic number.

21409835280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21409835280 is an abundant number, since it is smaller than the sum of its proper divisors (44960654832).

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

21409835280 is a wasteful number, since it uses less digits than its factorization.

21409835280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89207663 (or 89207657 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 42.

The spelling of 21409835280 in words is "twenty-one billion, four hundred nine million, eight hundred thirty-five thousand, two hundred eighty".