1211243345 has 16 divisors (see below), whose sum is σ = 1598607360. Its totient is φ = 875423424.

The previous prime is 1211243339. The next prime is 1211243347. The reversal of 1211243345 is 5433421121.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1211243345 - 2¹⁸ = 1210981201 is a prime.

It is a super-2 number, since 2×1211243345² = 2934220881613578050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1211243347) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 195185 + ... + 201294.

It is an arithmetic number, because the mean of its divisors is an integer number (99912960).

Almost surely, 2^1211243345 is an apocalyptic number.

It is an amenable number.

1211243345 is a deficient number, since it is larger than the sum of its proper divisors (387364015).

1211243345 is a wasteful number, since it uses less digits than its factorization.

1211243345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396544.

The product of its digits is 2880, while the sum is 26.

The square root of 1211243345 is about 34802.9215009315. The cubic root of 1211243345 is about 1065.9671011369.

Adding to 1211243345 its reverse (5433421121), we get a palindrome (6644664466).

The spelling of 1211243345 in words is "one billion, two hundred eleven million, two hundred forty-three thousand, three hundred forty-five".