21340431024 has 80 divisors (see below), whose sum is σ = 63678960000. Its totient is φ = 6086394880.

The previous prime is 21340431023. The next prime is 21340431061. The reversal of 21340431024 is 42013404312.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a junction number, because it is equal to n+sod(n) for n = 21340430985 and 21340431003.

It is not an unprimeable number, because it can be changed into a prime (21340431023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1179774 + ... + 1197725.

It is an arithmetic number, because the mean of its divisors is an integer number (795987000).

Almost surely, 2^21340431024 is an apocalyptic number.

21340431024 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21340431024 is an abundant number, since it is smaller than the sum of its proper divisors (42338528976).

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

21340431024 is a wasteful number, since it uses less digits than its factorization.

21340431024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2377538 (or 2377532 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 21340431024 its reverse (42013404312), we get a palindrome (63353835336).

The spelling of 21340431024 in words is "twenty-one billion, three hundred forty million, four hundred thirty-one thousand, twenty-four".