1221103232550 has 120 divisors (see below), whose sum is σ = 3423986319600. Its totient is φ = 322640003520.

The previous prime is 1221103232533. The next prime is 1221103232603. The reversal of 1221103232550 is 552323011221.

1221103232550 is a `hidden beast` number, since 1 + 2 + 2 + 1 + 103 + 2 + 3 + 2 + 550 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 941610 + ... + 1824509.

It is an arithmetic number, because the mean of its divisors is an integer number (28533219330).

Almost surely, 2^{1221103232550} is an apocalyptic number.

1221103232550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221103232550 is an abundant number, since it is smaller than the sum of its proper divisors (2202883087050).

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

1221103232550 is a wasteful number, since it uses less digits than its factorization.

1221103232550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2766252 (or 2766238 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

Adding to 1221103232550 its reverse (552323011221), we get a palindrome (1773426243771).

The spelling of 1221103232550 in words is "one trillion, two hundred twenty-one billion, one hundred three million, two hundred thirty-two thousand, five hundred fifty".