21221563241340 has 288 divisors, whose sum is σ = 80767287304704. Its totient is φ = 4381587924480.

The previous prime is 21221563241339. The next prime is 21221563241371. The reversal of 21221563241340 is 4314236512212.

It is a happy number.

21221563241340 is a `hidden beast` number, since 2 + 1 + 2 + 2 + 1 + 5 + 632 + 4 + 13 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 21221563241295 and 21221563241304.

It is a congruent number.

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, 2700214 + ... + 7052253.

It is an arithmetic number, because the mean of its divisors is an integer number (280441969808).

Almost surely, 2^{21221563241340} is an apocalyptic number.

21221563241340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221563241340 is an abundant number, since it is smaller than the sum of its proper divisors (59545724063364).

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

21221563241340 is a wasteful number, since it uses less digits than its factorization.

21221563241340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9752657 (or 9752652 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

Adding to 21221563241340 its reverse (4314236512212), we get a palindrome (25535799753552).

The spelling of 21221563241340 in words is "twenty-one trillion, two hundred twenty-one billion, five hundred sixty-three million, two hundred forty-one thousand, three hundred forty".