129227731 has 4 divisors (see below), whose sum is σ = 134846352. Its totient is φ = 123609112.

The previous prime is 129227719. The next prime is 129227737. The reversal of 129227731 is 137722921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 137722921 = 7 ⋅19674703.

It is a cyclic number.

It is not a de Polignac number, because 129227731 - 2⁵ = 129227699 is a prime.

It is a super-2 number, since 2×129227731² = 33399612918816722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129227737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2809276 + ... + 2809321.

It is an arithmetic number, because the mean of its divisors is an integer number (33711588).

Almost surely, 2^129227731 is an apocalyptic number.

129227731 is a deficient number, since it is larger than the sum of its proper divisors (5618621).

129227731 is an equidigital number, since it uses as much as digits as its factorization.

129227731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5618620.

The product of its digits is 10584, while the sum is 34.

The square root of 129227731 is about 11367.8375692125. The cubic root of 129227731 is about 505.5745915431.

The spelling of 129227731 in words is "one hundred twenty-nine million, two hundred twenty-seven thousand, seven hundred thirty-one".