1556001551189 has 2 divisors, whose sum is σ = 1556001551190. Its totient is φ = 1556001551188.

The previous prime is 1556001551141. The next prime is 1556001551191. The reversal of 1556001551189 is 9811551006551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1390885292164 + 165116259025 = 1179358^2 + 406345^2 .

It is a cyclic number.

It is not a de Polignac number, because 1556001551189 - 2²⁰ = 1556000502613 is a prime.

It is a super-2 number, since 2×1556001551189² (a number of 25 digits) contains 22 as substring.

Together with 1556001551191, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1556001551989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 778000775594 + 778000775595.

It is an arithmetic number, because the mean of its divisors is an integer number (778000775595).

Almost surely, 2^{1556001551189} is an apocalyptic number.

It is an amenable number.

1556001551189 is a deficient number, since it is larger than the sum of its proper divisors (1).

1556001551189 is an equidigital number, since it uses as much as digits as its factorization.

1556001551189 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 270000, while the sum is 47.

The spelling of 1556001551189 in words is "one trillion, five hundred fifty-six billion, one million, five hundred fifty-one thousand, one hundred eighty-nine".