1020400002001 has 2 divisors, whose sum is σ = 1020400002002. Its totient is φ = 1020400002000.

The previous prime is 1020400001963. The next prime is 1020400002049. The reversal of 1020400002001 is 1002000040201.

1020400002001 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., 970715592001 + 49684410000 = 985249^2 + 222900^2 .

It is a cyclic number.

It is not a de Polignac number, because 1020400002001 - 2¹⁷ = 1020399870929 is a prime.

It is not a weakly prime, because it can be changed into another prime (1020400002091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510200001000 + 510200001001.

It is an arithmetic number, because the mean of its divisors is an integer number (510200001001).

Almost surely, 2^{1020400002001} is an apocalyptic number.

It is an amenable number.

1020400002001 is a deficient number, since it is larger than the sum of its proper divisors (1).

1020400002001 is an equidigital number, since it uses as much as digits as its factorization.

1020400002001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 1020400002001 its reverse (1002000040201), we get a palindrome (2022400042202).

The spelling of 1020400002001 in words is "one trillion, twenty billion, four hundred million, two thousand, one".