491501690 has 32 divisors (see below), whose sum is σ = 933733440. Its totient is φ = 185760000.

The previous prime is 491501687. The next prime is 491501693. The reversal of 491501690 is 96105194.

It is an interprime number because it is at equal distance from previous prime (491501687) and next prime (491501693).

It is a super-2 number, since 2×491501690² = 483147822545712200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 491501690.

It is not an unprimeable number, because it can be changed into a prime (491501693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72965 + ... + 79415.

It is an arithmetic number, because the mean of its divisors is an integer number (29179170).

Almost surely, 2^491501690 is an apocalyptic number.

491501690 is a deficient number, since it is larger than the sum of its proper divisors (442231750).

491501690 is a wasteful number, since it uses less digits than its factorization.

491501690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6878.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 491501690 is about 22169.8373922769. The cubic root of 491501690 is about 789.1780641104.

The spelling of 491501690 in words is "four hundred ninety-one million, five hundred one thousand, six hundred ninety".