1553660641061 has 2 divisors, whose sum is σ = 1553660641062. Its totient is φ = 1553660641060.

The previous prime is 1553660640991. The next prime is 1553660641087. The reversal of 1553660641061 is 1601460663551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1380942268225 + 172718372836 = 1175135^2 + 415594^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1553660641061 is a prime.

It is a super-2 number, since 2×1553660641061² (a number of 25 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1553660641961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 776830320530 + 776830320531.

It is an arithmetic number, because the mean of its divisors is an integer number (776830320531).

Almost surely, 2^{1553660641061} is an apocalyptic number.

It is an amenable number.

1553660641061 is a deficient number, since it is larger than the sum of its proper divisors (1).

1553660641061 is an equidigital number, since it uses as much as digits as its factorization.

1553660641061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 388800, while the sum is 44.

The spelling of 1553660641061 in words is "one trillion, five hundred fifty-three billion, six hundred sixty million, six hundred forty-one thousand, sixty-one".