1000001999873 has 2 divisors, whose sum is σ = 1000001999874. Its totient is φ = 1000001999872.

The previous prime is 1000001999831. The next prime is 1000001999879. The reversal of 1000001999873 is 3789991000001.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 614102620609 + 385899379264 = 783647^2 + 621208^2 .

It is a cyclic number.

It is not a de Polignac number, because 1000001999873 - 2¹² = 1000001995777 is a prime.

It is a super-2 number, since 2×1000001999873² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1000001999879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500000999936 + 500000999937.

It is an arithmetic number, because the mean of its divisors is an integer number (500000999937).

Almost surely, 2^{1000001999873} is an apocalyptic number.

It is an amenable number.

1000001999873 is a deficient number, since it is larger than the sum of its proper divisors (1).

1000001999873 is an equidigital number, since it uses as much as digits as its factorization.

1000001999873 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 122472, while the sum is 47.

Adding to 1000001999873 its reverse (3789991000001), we get a palindrome (4789992999874).

The spelling of 1000001999873 in words is "one trillion, one million, nine hundred ninety-nine thousand, eight hundred seventy-three".