491090251 has 8 divisors (see below), whose sum is σ = 519297408. Its totient is φ = 463656000.

The previous prime is 491090239. The next prime is 491090261. The reversal of 491090251 is 152090194.

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 491090251 - 2⁵ = 491090219 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491090261) 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, 191920 + ... + 194461.

It is an arithmetic number, because the mean of its divisors is an integer number (64912176).

Almost surely, 2^491090251 is an apocalyptic number.

491090251 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

491090251 is a deficient number, since it is larger than the sum of its proper divisors (28207157).

491090251 is a wasteful number, since it uses less digits than its factorization.

491090251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386453.

The product of its (nonzero) digits is 3240, while the sum is 31.

The square root of 491090251 is about 22160.5561978936. The cubic root of 491090251 is about 788.9577940790.

The spelling of 491090251 in words is "four hundred ninety-one million, ninety thousand, two hundred fifty-one".