1211250155 has 8 divisors (see below), whose sum is σ = 1468485312. Its totient is φ = 959010048.

The previous prime is 1211250151. The next prime is 1211250191. The reversal of 1211250155 is 5510521121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1211250155 - 2² = 1211250151 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 1211250155.

It is not an unprimeable number, because it can be changed into a prime (1211250151) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1248227 + ... + 1249196.

It is an arithmetic number, because the mean of its divisors is an integer number (183560664).

Almost surely, 2^1211250155 is an apocalyptic number.

1211250155 is a deficient number, since it is larger than the sum of its proper divisors (257235157).

1211250155 is an equidigital number, since it uses as much as digits as its factorization.

1211250155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2497525.

The product of its (nonzero) digits is 500, while the sum is 23.

The square root of 1211250155 is about 34803.0193374081. The cubic root of 1211250155 is about 1065.9690988699.

Adding to 1211250155 its reverse (5510521121), we get a palindrome (6721771276).

The spelling of 1211250155 in words is "one billion, two hundred eleven million, two hundred fifty thousand, one hundred fifty-five".