1221450205455 has 48 divisors (see below), whose sum is σ = 2174566698720. Its totient is φ = 633785451264.

The previous prime is 1221450205453. The next prime is 1221450205471. The reversal of 1221450205455 is 5545020541221.

1221450205455 is a `hidden beast` number, since 122 + 14 + 50 + 20 + 5 + 455 = 666.

It is not a de Polignac number, because 1221450205455 - 2¹ = 1221450205453 is a prime.

It is a super-3 number, since 3×1221450205455³ (a number of 37 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221450205453) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 35418961 + ... + 35453429.

It is an arithmetic number, because the mean of its divisors is an integer number (45303472890).

Almost surely, 2^{1221450205455} is an apocalyptic number.

1221450205455 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1221450205455 is a deficient number, since it is larger than the sum of its proper divisors (953116493265).

1221450205455 is a wasteful number, since it uses less digits than its factorization.

1221450205455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55800 (or 55797 counting only the distinct ones).

The product of its (nonzero) digits is 80000, while the sum is 36.

Adding to 1221450205455 its reverse (5545020541221), we get a palindrome (6766470746676).

The spelling of 1221450205455 in words is "one trillion, two hundred twenty-one billion, four hundred fifty million, two hundred five thousand, four hundred fifty-five".