22138729 has 8 divisors (see below), whose sum is σ = 22740480. Its totient is φ = 21540000.

The previous prime is 22138651. The next prime is 22138733. The reversal of 22138729 is 92783122.

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

It is a cyclic number.

It is not a de Polignac number, because 22138729 - 2¹⁹ = 21614441 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22138694 and 22138703.

It is not an unprimeable number, because it can be changed into a prime (22138759) 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, 29104 + ... + 29854.

It is an arithmetic number, because the mean of its divisors is an integer number (2842560).

Almost surely, 2^22138729 is an apocalyptic number.

It is an amenable number.

22138729 is a deficient number, since it is larger than the sum of its proper divisors (601751).

22138729 is an equidigital number, since it uses as much as digits as its factorization.

22138729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1511.

The product of its digits is 12096, while the sum is 34.

The square root of 22138729 is about 4705.1810804686. The cubic root of 22138729 is about 280.7916753146.

The spelling of 22138729 in words is "twenty-two million, one hundred thirty-eight thousand, seven hundred twenty-nine".