1001240155 has 4 divisors (see below), whose sum is σ = 1201488192. Its totient is φ = 800992120.

The previous prime is 1001240147. The next prime is 1001240159. The reversal of 1001240155 is 5510421001.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1001240155 - 2³ = 1001240147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1001240159) 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, 100124011 + ... + 100124020.

It is an arithmetic number, because the mean of its divisors is an integer number (300372048).

Almost surely, 2^1001240155 is an apocalyptic number.

1001240155 is a deficient number, since it is larger than the sum of its proper divisors (200248037).

1001240155 is an equidigital number, since it uses as much as digits as its factorization.

1001240155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200248036.

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

The square root of 1001240155 is about 31642.3790982916. The cubic root of 1001240155 is about 1000.4132142305.

Adding to 1001240155 its reverse (5510421001), we get a palindrome (6511661156).

The spelling of 1001240155 in words is "one billion, one million, two hundred forty thousand, one hundred fifty-five".