1555421240240 has 40 divisors (see below), whose sum is σ = 4132976439840. Its totient is φ = 533287282176.

The previous prime is 1555421240239. The next prime is 1555421240267. The reversal of 1555421240240 is 420421245551.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 1555421240240.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1388768405 + ... + 1388769524.

It is an arithmetic number, because the mean of its divisors is an integer number (103324410996).

Almost surely, 2^{1555421240240} is an apocalyptic number.

1555421240240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1555421240240 is an abundant number, since it is smaller than the sum of its proper divisors (2577555199600).

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

1555421240240 is a wasteful number, since it uses less digits than its factorization.

1555421240240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2777537949 (or 2777537943 counting only the distinct ones).

The product of its (nonzero) digits is 64000, while the sum is 35.

Adding to 1555421240240 its reverse (420421245551), we get a palindrome (1975842485791).

The spelling of 1555421240240 in words is "one trillion, five hundred fifty-five billion, four hundred twenty-one million, two hundred forty thousand, two hundred forty".