1020666516563 has 4 divisors (see below), whose sum is σ = 1020684928488. Its totient is φ = 1020648104640.

The previous prime is 1020666516557. The next prime is 1020666516589. The reversal of 1020666516563 is 3656156660201.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1020666516563 - 2¹⁴ = 1020666500179 is a prime.

It is a super-3 number, since 3×1020666516563³ (a number of 37 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1020666516503) 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, 9122558 + ... + 9233763.

It is an arithmetic number, because the mean of its divisors is an integer number (255171232122).

Almost surely, 2^{1020666516563} is an apocalyptic number.

1020666516563 is a deficient number, since it is larger than the sum of its proper divisors (18411925).

1020666516563 is an equidigital number, since it uses as much as digits as its factorization.

1020666516563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18411924.

The product of its (nonzero) digits is 1166400, while the sum is 47.

The spelling of 1020666516563 in words is "one trillion, twenty billion, six hundred sixty-six million, five hundred sixteen thousand, five hundred sixty-three".