491029409 has 8 divisors (see below), whose sum is σ = 533482152. Its totient is φ = 449245440.

The previous prime is 491029403. The next prime is 491029417. The reversal of 491029409 is 904920194.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 10543009 + 480486400 = 3247^2 + 21920^2 .

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 491029409 - 2²⁸ = 222593953 is a prime.

It is a super-2 number, since 2×491029409² = 482219761005778562, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491029403) 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, 165662 + ... + 168599.

It is an arithmetic number, because the mean of its divisors is an integer number (66685269).

Almost surely, 2^491029409 is an apocalyptic number.

It is an amenable number.

491029409 is a deficient number, since it is larger than the sum of its proper divisors (42452743).

491029409 is a wasteful number, since it uses less digits than its factorization.

491029409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334387.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 491029409 is about 22159.1834010191. The cubic root of 491029409 is about 788.9252109625.

It can be divided in two parts, 491029 and 409, that multiplied together give a triangular number (200830861 = T₂₀₀₄₁).

The spelling of 491029409 in words is "four hundred ninety-one million, twenty-nine thousand, four hundred nine".