21201313240 has 32 divisors (see below), whose sum is σ = 47952725760. Its totient is φ = 8436121600.

The previous prime is 21201313223. The next prime is 21201313303. The reversal of 21201313240 is 4231310212.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1379881 + ... + 1395160.

It is an arithmetic number, because the mean of its divisors is an integer number (1498522680).

Almost surely, 2^21201313240 is an apocalyptic number.

21201313240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201313240 is an abundant number, since it is smaller than the sum of its proper divisors (26751412520).

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

21201313240 is a wasteful number, since it uses less digits than its factorization.

21201313240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2775243 (or 2775239 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21201313240 its reverse (4231310212), we get a palindrome (25432623452).

The spelling of 21201313240 in words is "twenty-one billion, two hundred one million, three hundred thirteen thousand, two hundred forty".