2228138729 has 4 divisors (see below), whose sum is σ = 2275545984. Its totient is φ = 2180731476.

The previous prime is 2228138719. The next prime is 2228138743. The reversal of 2228138729 is 9278318222.

2228138729 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2228138729 - 2⁴ = 2228138713 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2228138729.

It is not an unprimeable number, because it can be changed into a prime (2228138719) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23703557 + ... + 23703650.

It is an arithmetic number, because the mean of its divisors is an integer number (568886496).

Almost surely, 2^2228138729 is an apocalyptic number.

It is an amenable number.

2228138729 is a deficient number, since it is larger than the sum of its proper divisors (47407255).

2228138729 is an equidigital number, since it uses as much as digits as its factorization.

2228138729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47407254.

The product of its digits is 193536, while the sum is 44.

The square root of 2228138729 is about 47203.1643960445. The cubic root of 2228138729 is about 1306.1129711527.

The spelling of 2228138729 in words is "two billion, two hundred twenty-eight million, one hundred thirty-eight thousand, seven hundred twenty-nine".