21244101221 has 8 divisors (see below), whose sum is σ = 25707147840. Its totient is φ = 17138098368.

The previous prime is 21244101217. The next prime is 21244101233. The reversal of 21244101221 is 12210144212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21244101221 - 2² = 21244101217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21244101193 and 21244101202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21244101121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89260811 + ... + 89261048.

It is an arithmetic number, because the mean of its divisors is an integer number (3213393480).

Almost surely, 2^21244101221 is an apocalyptic number.

It is an amenable number.

21244101221 is a deficient number, since it is larger than the sum of its proper divisors (4463046619).

21244101221 is a wasteful number, since it uses less digits than its factorization.

21244101221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178521883.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21244101221 its reverse (12210144212), we get a palindrome (33454245433).

The spelling of 21244101221 in words is "twenty-one billion, two hundred forty-four million, one hundred one thousand, two hundred twenty-one".