1211549145 has 8 divisors (see below), whose sum is σ = 1938478656. Its totient is φ = 646159536.

The previous prime is 1211549113. The next prime is 1211549147. The reversal of 1211549145 is 5419451121.

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

It is not a de Polignac number, because 1211549145 - 2⁵ = 1211549113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1211549147) 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, 40384957 + ... + 40384986.

It is an arithmetic number, because the mean of its divisors is an integer number (242309832).

Almost surely, 2^1211549145 is an apocalyptic number.

1211549145 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1211549145 is a deficient number, since it is larger than the sum of its proper divisors (726929511).

1211549145 is an equidigital number, since it uses as much as digits as its factorization.

1211549145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80769951.

The product of its digits is 7200, while the sum is 33.

The square root of 1211549145 is about 34807.3145330116. The cubic root of 1211549145 is about 1066.0568010617.

The spelling of 1211549145 in words is "one billion, two hundred eleven million, five hundred forty-nine thousand, one hundred forty-five".