1155402001 has 4 divisors (see below), whose sum is σ = 1244279092. Its totient is φ = 1066524912.

The previous prime is 1155401993. The next prime is 1155402011. The reversal of 1155402001 is 1002045511.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1002045511 = 523 ⋅1915957.

It can be written as a sum of positive squares in 2 ways, for example, as 227285776 + 928116225 = 15076^2 + 30465^2 .

It is a cyclic number.

It is not a de Polignac number, because 1155402001 - 2³ = 1155401993 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1155402001.

It is not an unprimeable number, because it can be changed into a prime (1155402011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44438526 + ... + 44438551.

It is an arithmetic number, because the mean of its divisors is an integer number (311069773).

Almost surely, 2^1155402001 is an apocalyptic number.

It is an amenable number.

1155402001 is a deficient number, since it is larger than the sum of its proper divisors (88877091).

1155402001 is an equidigital number, since it uses as much as digits as its factorization.

1155402001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88877090.

The product of its (nonzero) digits is 200, while the sum is 19.

The square root of 1155402001 is about 33991.2047594668. The cubic root of 1155402001 is about 1049.3274607803.

Adding to 1155402001 its reverse (1002045511), we get a palindrome (2157447512).

The spelling of 1155402001 in words is "one billion, one hundred fifty-five million, four hundred two thousand, one".