1016721056569 has 8 divisors (see below), whose sum is σ = 1029220846920. Its totient is φ = 1004262452736.

The previous prime is 1016721056539. The next prime is 1016721056599. The reversal of 1016721056569 is 9656501276101.

1016721056569 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1016721056539) and next prime (1016721056599).

It can be written as a sum of positive squares in 4 ways, for example, as 440913264169 + 575807792400 = 664013^2 + 758820^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1016721056569 - 2⁵ = 1016721056537 is a prime.

It is a super-2 number, since 2×1016721056569² (a number of 25 digits) contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1016721056539) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10246954 + ... + 10345699.

It is an arithmetic number, because the mean of its divisors is an integer number (128652605865).

Almost surely, 2^{1016721056569} is an apocalyptic number.

It is an amenable number.

1016721056569 is a deficient number, since it is larger than the sum of its proper divisors (12499790351).

1016721056569 is an equidigital number, since it uses as much as digits as its factorization.

1016721056569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20593259.

The product of its (nonzero) digits is 680400, while the sum is 49.

The spelling of 1016721056569 in words is "one trillion, sixteen billion, seven hundred twenty-one million, fifty-six thousand, five hundred sixty-nine".