491637 has 8 divisors (see below), whose sum is σ = 678240. Its totient is φ = 316400.

The previous prime is 491633. The next prime is 491639. The reversal of 491637 is 736194.

It is a happy number.

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 491637 - 2² = 491633 is a prime.

It is an Ulam number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 491637.

It is not an unprimeable number, because it can be changed into a prime (491633) 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, 2739 + ... + 2912.

It is an arithmetic number, because the mean of its divisors is an integer number (84780).

2⁴⁹¹⁶³⁷ is an apocalyptic number.

It is an amenable number.

491637 is a deficient number, since it is larger than the sum of its proper divisors (186603).

491637 is a wasteful number, since it uses less digits than its factorization.

491637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5683.

The product of its digits is 4536, while the sum is 30.

The square root of 491637 is about 701.1683107500. The cubic root of 491637 is about 78.9250477484.

It can be divided in two parts, 491 and 637, that added together give a triangular number (1128 = T₄₇).

The spelling of 491637 in words is "four hundred ninety-one thousand, six hundred thirty-seven".