1555500000001 has 4 divisors (see below), whose sum is σ = 1555831597104. Its totient is φ = 1555168402900.

The previous prime is 1555499999923. The next prime is 1555500000023. The reversal of 1555500000001 is 1000000055551.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1555500000001 - 2⁷ = 1555499999873 is a prime.

It is a super-2 number, since 2×1555500000001² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1555500000071) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 165791515 + ... + 165800896.

It is an arithmetic number, because the mean of its divisors is an integer number (388957899276).

Almost surely, 2^{1555500000001} is an apocalyptic number.

It is an amenable number.

1555500000001 is a deficient number, since it is larger than the sum of its proper divisors (331597103).

1555500000001 is an equidigital number, since it uses as much as digits as its factorization.

1555500000001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331597102.

The product of its (nonzero) digits is 625, while the sum is 22.

Adding to 1555500000001 its reverse (1000000055551), we get a palindrome (2555500055552).

The spelling of 1555500000001 in words is "one trillion, five hundred fifty-five billion, five hundred million, one", and thus it is an aban number.