1553550021440 has 28 divisors (see below), whose sum is σ = 3699390989316. Its totient is φ = 621420008448.

The previous prime is 1553550021433. The next prime is 1553550021473. The reversal of 1553550021440 is 441200553551.

It can be written as a sum of positive squares in 2 ways, for example, as 1034158828096 + 519391193344 = 1016936^2 + 720688^2 .

It is a super-3 number, since 3×1553550021440³ (a number of 38 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1553550021440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2427421589 + ... + 2427422228.

Almost surely, 2^{1553550021440} is an apocalyptic number.

1553550021440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1553550021440 is an abundant number, since it is smaller than the sum of its proper divisors (2145840967876).

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

1553550021440 is an equidigital number, since it uses as much as digits as its factorization.

1553550021440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4854843834 (or 4854843824 counting only the distinct ones).

The product of its (nonzero) digits is 60000, while the sum is 35.

Adding to 1553550021440 its reverse (441200553551), we get a palindrome (1994750574991).

The spelling of 1553550021440 in words is "one trillion, five hundred fifty-three billion, five hundred fifty million, twenty-one thousand, four hundred forty".