21621554136101 has 8 divisors (see below), whose sum is σ = 24098326591680. Its totient is φ = 19278661272768.

The previous prime is 21621554136041. The next prime is 21621554136109. The reversal of 21621554136101 is 10163145512612.

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 21621554136101 - 2¹⁴ = 21621554119717 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21621554136109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33469897721 + ... + 33469898366.

It is an arithmetic number, because the mean of its divisors is an integer number (3012290823960).

Almost surely, 2^{21621554136101} is an apocalyptic number.

It is an amenable number.

21621554136101 is a deficient number, since it is larger than the sum of its proper divisors (2476772455579).

21621554136101 is a wasteful number, since it uses less digits than its factorization.

21621554136101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66939796123.

The product of its (nonzero) digits is 43200, while the sum is 38.

Adding to 21621554136101 its reverse (10163145512612), we get a palindrome (31784699648713).

The spelling of 21621554136101 in words is "twenty-one trillion, six hundred twenty-one billion, five hundred fifty-four million, one hundred thirty-six thousand, one hundred one".