2121147729 has 24 divisors (see below), whose sum is σ = 3263245440. Its totient is φ = 1375873776.

The previous prime is 2121147719. The next prime is 2121147757. The reversal of 2121147729 is 9277411212.

It is not a de Polignac number, because 2121147729 - 2⁵ = 2121147697 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2121147693 and 2121147702.

It is not an unprimeable number, because it can be changed into a prime (2121147719) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 108969 + ... + 126950.

It is an arithmetic number, because the mean of its divisors is an integer number (135968560).

Almost surely, 2^2121147729 is an apocalyptic number.

It is an amenable number.

2121147729 is a deficient number, since it is larger than the sum of its proper divisors (1142097711).

2121147729 is an equidigital number, since it uses as much as digits as its factorization.

2121147729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235971 (or 235959 counting only the distinct ones).

The product of its digits is 14112, while the sum is 36.

The square root of 2121147729 is about 46055.9195869543. The cubic root of 2121147729 is about 1284.8634412054.

The spelling of 2121147729 in words is "two billion, one hundred twenty-one million, one hundred forty-seven thousand, seven hundred twenty-nine".