21430335828 has 96 divisors (see below), whose sum is σ = 57491965440. Its totient is φ = 6144647040.

The previous prime is 21430335799. The next prime is 21430335851. The reversal of 21430335828 is 82853303412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2209726 + ... + 2219402.

It is an arithmetic number, because the mean of its divisors is an integer number (598874640).

Almost surely, 2^21430335828 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21430335828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28745982720).

21430335828 is an abundant number, since it is smaller than the sum of its proper divisors (36061629612).

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

21430335828 is a wasteful number, since it uses less digits than its factorization.

21430335828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10597 (or 10595 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 39.

The spelling of 21430335828 in words is "twenty-one billion, four hundred thirty million, three hundred thirty-five thousand, eight hundred twenty-eight".