1002003002001 has 9 divisors (see below), whose sum is σ = 1447342007241. Its totient is φ = 667999999332.

The previous prime is 1002003001949. The next prime is 1002003002027.

It is a happy number.

The square root of 1002003002001 is 1001001.

It is a perfect power (a square), and thus also a powerful number.

1002003002001 is nontrivially palindromic in base 10.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 1002003002001 - 2¹¹ = 1002002999953 is a prime.

It is a super-4 number, since 4×1002003002001⁴ (a number of 49 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (1002003002041) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2836170 + ... + 3169836.

Almost surely, 2^{1002003002001} is an apocalyptic number.

1002003002001 is the 1001001-st square number.

1002003002001 is the 500501-st centered octagonal number.

It is an amenable number.

1002003002001 is a deficient number, since it is larger than the sum of its proper divisors (445339005240).

1002003002001 is an frugal number, since it uses more digits than its factorization.

1002003002001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 667340 (or 333670 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The spelling of 1002003002001 in words is "one trillion, two billion, three million, two thousand, one".