1243405155 has 32 divisors (see below), whose sum is σ = 2062609920. Its totient is φ = 639153920.

The previous prime is 1243405153. The next prime is 1243405159. The reversal of 1243405155 is 5515043421.

1243405155 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1243405155 - 2¹ = 1243405153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1243405153) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38866 + ... + 63224.

It is an arithmetic number, because the mean of its divisors is an integer number (64456560).

Almost surely, 2^1243405155 is an apocalyptic number.

1243405155 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1243405155 is a deficient number, since it is larger than the sum of its proper divisors (819204765).

1243405155 is a wasteful number, since it uses less digits than its factorization.

1243405155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24491.

The product of its (nonzero) digits is 12000, while the sum is 30.

The square root of 1243405155 is about 35261.9505274453. The cubic root of 1243405155 is about 1075.3195819260.

Adding to 1243405155 its reverse (5515043421), we get a palindrome (6758448576).

The spelling of 1243405155 in words is "one billion, two hundred forty-three million, four hundred five thousand, one hundred fifty-five".