21232242340 has 12 divisors (see below), whose sum is σ = 44587708956. Its totient is φ = 8492896928.

The previous prime is 21232242337. The next prime is 21232242347. The reversal of 21232242340 is 4324223212.

It can be written as a sum of positive squares in 2 ways, for example, as 16488614464 + 4743627876 = 128408^2 + 68874^2 .

It is a super-2 number, since 2×21232242340² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21232242347) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 530806039 + ... + 530806078.

It is an arithmetic number, because the mean of its divisors is an integer number (3715642413).

Almost surely, 2^21232242340 is an apocalyptic number.

21232242340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21232242340 is an abundant number, since it is smaller than the sum of its proper divisors (23355466616).

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

21232242340 is a wasteful number, since it uses less digits than its factorization.

21232242340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1061612126 (or 1061612124 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 25.

Adding to 21232242340 its reverse (4324223212), we get a palindrome (25556465552).

The spelling of 21232242340 in words is "twenty-one billion, two hundred thirty-two million, two hundred forty-two thousand, three hundred forty".