1320421535550 has 288 divisors, whose sum is σ = 3898190499840. Its totient is φ = 318477312000.

The previous prime is 1320421535539. The next prime is 1320421535569. The reversal of 1320421535550 is 555351240231.

1320421535550 is a `hidden beast` number, since 1 + 3 + 20 + 42 + 15 + 35 + 550 = 666.

It is a super-3 number, since 3×1320421535550³ (a number of 37 digits) contains 333 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 57300931 + ... + 57323969.

It is an arithmetic number, because the mean of its divisors is an integer number (13535383680).

Almost surely, 2^{1320421535550} is an apocalyptic number.

1320421535550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1320421535550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1949095249920).

1320421535550 is an abundant number, since it is smaller than the sum of its proper divisors (2577768964290).

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

1320421535550 is a wasteful number, since it uses less digits than its factorization.

1320421535550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23268 (or 23260 counting only the distinct ones).

The product of its (nonzero) digits is 90000, while the sum is 36.

Adding to 1320421535550 its reverse (555351240231), we get a palindrome (1875772775781).

The spelling of 1320421535550 in words is "one trillion, three hundred twenty billion, four hundred twenty-one million, five hundred thirty-five thousand, five hundred fifty".