21230255340 has 288 divisors, whose sum is σ = 80842245120. Its totient is φ = 4397234688.

The previous prime is 21230255329. The next prime is 21230255369. The reversal of 21230255340 is 4355203212.

It is a happy number.

21230255340 is a `hidden beast` number, since 2 + 12 + 302 + 5 + 5 + 340 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 531342 + ... + 569898.

It is an arithmetic number, because the mean of its divisors is an integer number (280702240).

Almost surely, 2^21230255340 is an apocalyptic number.

21230255340 is a gapful number since it is divisible by the number (20) 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 21230255340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40421122560).

21230255340 is an abundant number, since it is smaller than the sum of its proper divisors (59611989780).

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

21230255340 is a wasteful number, since it uses less digits than its factorization.

21230255340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38621 (or 38616 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 27.

Adding to 21230255340 its reverse (4355203212), we get a palindrome (25585458552).

The spelling of 21230255340 in words is "twenty-one billion, two hundred thirty million, two hundred fifty-five thousand, three hundred forty".