21124232340 has 48 divisors (see below), whose sum is σ = 59285157120. Its totient is φ = 5620051840.

The previous prime is 21124232299. The next prime is 21124232341. The reversal of 21124232340 is 4323242112.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21124232340.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21124232341) 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, 382575 + ... + 434294.

It is an arithmetic number, because the mean of its divisors is an integer number (1235107440).

Almost surely, 2^21124232340 is an apocalyptic number.

21124232340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21124232340 is an abundant number, since it is smaller than the sum of its proper divisors (38160924780).

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

21124232340 is a wasteful number, since it uses less digits than its factorization.

21124232340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 817312 (or 817310 counting only the distinct ones).

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

Adding to 21124232340 its reverse (4323242112), we get a palindrome (25447474452).

The spelling of 21124232340 in words is "twenty-one billion, one hundred twenty-four million, two hundred thirty-two thousand, three hundred forty".