391129229 has 4 divisors (see below), whose sum is σ = 391175100. Its totient is φ = 391083360.

The previous prime is 391129199. The next prime is 391129261. The reversal of 391129229 is 922921193.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 212372329 + 178756900 = 14573^2 + 13370^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-391129229 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 391129192 and 391129201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391122229) 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, 5954 + ... + 28595.

It is an arithmetic number, because the mean of its divisors is an integer number (97793775).

Almost surely, 2^391129229 is an apocalyptic number.

It is an amenable number.

391129229 is a deficient number, since it is larger than the sum of its proper divisors (45871).

391129229 is a wasteful number, since it uses less digits than its factorization.

391129229 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45870.

The product of its digits is 17496, while the sum is 38.

The square root of 391129229 is about 19776.9873590494. The cubic root of 391129229 is about 731.3188325495.

The spelling of 391129229 in words is "three hundred ninety-one million, one hundred twenty-nine thousand, two hundred twenty-nine".