1555156661156 has 72 divisors (see below), whose sum is σ = 3295116155520. Its totient is φ = 639564787008.

The previous prime is 1555156661119. The next prime is 1555156661159. The reversal of 1555156661156 is 6511666515551.

It is a junction number, because it is equal to n+sod(n) for n = 1555156661098 and 1555156661107.

It is not an unprimeable number, because it can be changed into a prime (1555156661159) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 87221 + ... + 1765763.

It is an arithmetic number, because the mean of its divisors is an integer number (45765502160).

Almost surely, 2^{1555156661156} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1555156661156, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1647558077760).

1555156661156 is an abundant number, since it is smaller than the sum of its proper divisors (1739959494364).

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

1555156661156 is a wasteful number, since it uses less digits than its factorization.

1555156661156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1678753 (or 1678744 counting only the distinct ones).

The product of its digits is 4050000, while the sum is 53.

The spelling of 1555156661156 in words is "one trillion, five hundred fifty-five billion, one hundred fifty-six million, six hundred sixty-one thousand, one hundred fifty-six".