491021451 has 6 divisors (see below), whose sum is σ = 709253220. Its totient is φ = 327347628.

The previous prime is 491021449. The next prime is 491021467. The reversal of 491021451 is 154120194.

It is not a de Polignac number, because 491021451 - 2¹ = 491021449 is a prime.

It is a super-2 number, since 2×491021451² = 482204130684290802, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (491021471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 27278961 + ... + 27278978.

It is an arithmetic number, because the mean of its divisors is an integer number (118208870).

Almost surely, 2^491021451 is an apocalyptic number.

491021451 is a deficient number, since it is larger than the sum of its proper divisors (218231769).

491021451 is a wasteful number, since it uses less digits than its factorization.

491021451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54557945 (or 54557942 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 491021451 is about 22159.0038359128. The cubic root of 491021451 is about 788.9209489634.

The spelling of 491021451 in words is "four hundred ninety-one million, twenty-one thousand, four hundred fifty-one".