21340869984 has 384 divisors, whose sum is σ = 73766246400. Its totient is φ = 5875752960.

The previous prime is 21340869971. The next prime is 21340869997. The reversal of 21340869984 is 48996804312.

It is an interprime number because it is at equal distance from previous prime (21340869971) and next prime (21340869997).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 21340869984.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 22068669 + ... + 22069635.

It is an arithmetic number, because the mean of its divisors is an integer number (192099600).

Almost surely, 2^21340869984 is an apocalyptic number.

21340869984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21340869984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36883123200).

21340869984 is an abundant number, since it is smaller than the sum of its proper divisors (52425376416).

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

21340869984 is a wasteful number, since it uses less digits than its factorization.

21340869984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1123 (or 1109 counting only the distinct ones).

The product of its (nonzero) digits is 2985984, while the sum is 54.

The spelling of 21340869984 in words is "twenty-one billion, three hundred forty million, eight hundred sixty-nine thousand, nine hundred eighty-four".