21551622676081 has 8 divisors (see below), whose sum is σ = 21773973316424. Its totient is φ = 21329275484160.

The previous prime is 21551622676027. The next prime is 21551622676109. The reversal of 21551622676081 is 18067622615512.

It can be written as a sum of positive squares in 4 ways, for example, as 1533300210225 + 20018322465856 = 1238265^2 + 4474184^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21551622676081 is a prime.

It is a super-2 number, since 2×21551622676081² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21551622676981) 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, 12815341 + ... + 14399173.

It is an arithmetic number, because the mean of its divisors is an integer number (2721746664553).

Almost surely, 2^{21551622676081} is an apocalyptic number.

It is an amenable number.

21551622676081 is a deficient number, since it is larger than the sum of its proper divisors (222350640343).

21551622676081 is a wasteful number, since it uses less digits than its factorization.

21551622676081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1724211.

The product of its (nonzero) digits is 2419200, while the sum is 52.

The spelling of 21551622676081 in words is "twenty-one trillion, five hundred fifty-one billion, six hundred twenty-two million, six hundred seventy-six thousand, eighty-one".