221534455605651 has 12 divisors (see below), whose sum is σ = 319994357925528. Its totient is φ = 147689570482944.

The previous prime is 221534455605647. The next prime is 221534455605703. The reversal of 221534455605651 is 156506554435122.

221534455605651 is a `hidden beast` number, since 2 + 2 + 1 + 5 + 34 + 4 + 556 + 0 + 5 + 6 + 51 = 666.

It is not a de Polignac number, because 221534455605651 - 2² = 221534455605647 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221534455607651) 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 11 ways as a sum of consecutive naturals, for example, 23557171 + ... + 31591283.

It is an arithmetic number, because the mean of its divisors is an integer number (26666196493794).

Almost surely, 2^{221534455605651} is an apocalyptic number.

221534455605651 is a deficient number, since it is larger than the sum of its proper divisors (98459902319877).

221534455605651 is a wasteful number, since it uses less digits than its factorization.

221534455605651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11097922 (or 11097919 counting only the distinct ones).

The product of its (nonzero) digits is 21600000, while the sum is 54.

The spelling of 221534455605651 in words is "two hundred twenty-one trillion, five hundred thirty-four billion, four hundred fifty-five million, six hundred five thousand, six hundred fifty-one".