1211730705 has 16 divisors (see below), whose sum is σ = 2154188160. Its totient is φ = 646256304.

The previous prime is 1211730703. The next prime is 1211730733. The reversal of 1211730705 is 5070371121.

It is a happy number.

It is not a de Polignac number, because 1211730705 - 2¹ = 1211730703 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (1211730703) 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, 4487757 + ... + 4488026.

It is an arithmetic number, because the mean of its divisors is an integer number (134636760).

Almost surely, 2^1211730705 is an apocalyptic number.

1211730705 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1211730705 is a deficient number, since it is larger than the sum of its proper divisors (942457455).

1211730705 is an equidigital number, since it uses as much as digits as its factorization.

1211730705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8975797 (or 8975791 counting only the distinct ones).

The product of its (nonzero) digits is 1470, while the sum is 27.

The square root of 1211730705 is about 34809.9225078138. The cubic root of 1211730705 is about 1066.1100506846.

The spelling of 1211730705 in words is "one billion, two hundred eleven million, seven hundred thirty thousand, seven hundred five".