221402763855 has 504 divisors, whose sum is σ = 529742753568. Its totient is φ = 86451515136.

The previous prime is 221402763833. The next prime is 221402763887. The reversal of 221402763855 is 558367204122.

221402763855 is a `hidden beast` number, since 2 + 2 + 1 + 4 + 0 + 2 + 7 + 638 + 5 + 5 = 666.

It is not a de Polignac number, because 221402763855 - 2²⁹ = 220865892943 is a prime.

It is a super-2 number, since 2×221402763855² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 221402763855.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 503 ways as a sum of consecutive naturals, for example, 5148901464 + ... + 5148901506.

It is an arithmetic number, because the mean of its divisors is an integer number (1051076892).

Almost surely, 2^221402763855 is an apocalyptic number.

221402763855 is an abundant number, since it is smaller than the sum of its proper divisors (308339989713).

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

221402763855 is an equidigital number, since it uses as much as digits as its factorization.

221402763855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 806400, while the sum is 45.

Adding to 221402763855 its reverse (558367204122), we get a palindrome (779769967977).

The spelling of 221402763855 in words is "two hundred twenty-one billion, four hundred two million, seven hundred sixty-three thousand, eight hundred fifty-five".