1000402040401 has 9 divisors (see below), whose sum is σ = 1045812949321. Its totient is φ = 956884295092.

The previous prime is 1000402040383. The next prime is 1000402040461. The reversal of 1000402040401 is 1040402040001.

The square root of 1000402040401 is 1000201.

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

It is a de Polignac number, because none of the positive numbers 2^k-1000402040401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1000402040461) 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, 22982880 + ... + 23026366.

Almost surely, 2^{1000402040401} is an apocalyptic number.

1000402040401 is the 1000201-st square number.

1000402040401 is the 500101-st centered octagonal number.

It is an amenable number.

1000402040401 is a deficient number, since it is larger than the sum of its proper divisors (45410908920).

1000402040401 is an frugal number, since it uses more digits than its factorization.

1000402040401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87020 (or 43510 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Multiplying 1000402040401 by its sum of digits (16), we get a square (16006432646416 = 4000804²).

Adding to 1000402040401 its reverse (1040402040001), we get a palindrome (2040804080402).

The spelling of 1000402040401 in words is "one trillion, four hundred two million, forty thousand, four hundred one".