1000002145561 has 2 divisors, whose sum is σ = 1000002145562. Its totient is φ = 1000002145560.

The previous prime is 1000002145559. The next prime is 1000002145627. The reversal of 1000002145561 is 1655412000001.

It is a happy number.

1000002145561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 878448809536 + 121553336025 = 937256^2 + 348645^2 .

It is an emirp because it is prime and its reverse (1655412000001) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1000002145561 - 2¹ = 1000002145559 is a prime.

It is a super-2 number, since 2×1000002145561² (a number of 25 digits) contains 22 as substring.

Together with 1000002145559, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1000002115561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500001072780 + 500001072781.

It is an arithmetic number, because the mean of its divisors is an integer number (500001072781).

Almost surely, 2^{1000002145561} is an apocalyptic number.

It is an amenable number.

1000002145561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1000002145561 is an equidigital number, since it uses as much as digits as its factorization.

1000002145561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1200, while the sum is 25.

Adding to 1000002145561 its reverse (1655412000001), we get a palindrome (2655414145562).

The spelling of 1000002145561 in words is "one trillion, two million, one hundred forty-five thousand, five hundred sixty-one".