1556004161893 has 2 divisors, whose sum is σ = 1556004161894. Its totient is φ = 1556004161892.

The previous prime is 1556004161851. The next prime is 1556004161909. The reversal of 1556004161893 is 3981614006551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1120111072609 + 435893089284 = 1058353^2 + 660222^2 .

It is a cyclic number.

It is not a de Polignac number, because 1556004161893 - 2⁹ = 1556004161381 is a prime.

It is a super-2 number, since 2×1556004161893² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1556004168893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 778002080946 + 778002080947.

It is an arithmetic number, because the mean of its divisors is an integer number (778002080947).

Almost surely, 2^{1556004161893} is an apocalyptic number.

It is an amenable number.

1556004161893 is a deficient number, since it is larger than the sum of its proper divisors (1).

1556004161893 is an equidigital number, since it uses as much as digits as its factorization.

1556004161893 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 777600, while the sum is 49.

The spelling of 1556004161893 in words is "one trillion, five hundred fifty-six billion, four million, one hundred sixty-one thousand, eight hundred ninety-three".