1211450155 has 8 divisors (see below), whose sum is σ = 1471255632. Its totient is φ = 957483168.

The previous prime is 1211450143. The next prime is 1211450173. The reversal of 1211450155 is 5510541121.

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 1211450155 - 2⁷ = 1211450027 is a prime.

It is a super-3 number, since 3×1211450155³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1459164 + ... + 1459993.

It is an arithmetic number, because the mean of its divisors is an integer number (183906954).

Almost surely, 2^1211450155 is an apocalyptic number.

1211450155 is a deficient number, since it is larger than the sum of its proper divisors (259805477).

1211450155 is an equidigital number, since it uses as much as digits as its factorization.

1211450155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2919245.

The product of its (nonzero) digits is 1000, while the sum is 25.

The square root of 1211450155 is about 34805.8925327307. The cubic root of 1211450155 is about 1066.0277661034.

Adding to 1211450155 its reverse (5510541121), we get a palindrome (6721991276).

The spelling of 1211450155 in words is "one billion, two hundred eleven million, four hundred fifty thousand, one hundred fifty-five".