491444971531 has 2 divisors, whose sum is σ = 491444971532. Its totient is φ = 491444971530.

The previous prime is 491444971489. The next prime is 491444971559. The reversal of 491444971531 is 135179444194.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 491444971531 - 2⁷ = 491444971403 is a prime.

It is a super-2 number, since 2×491444971531² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (491444971931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245722485765 + 245722485766.

It is an arithmetic number, because the mean of its divisors is an integer number (245722485766).

Almost surely, 2^491444971531 is an apocalyptic number.

491444971531 is a deficient number, since it is larger than the sum of its proper divisors (1).

491444971531 is an equidigital number, since it uses as much as digits as its factorization.

491444971531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2177280, while the sum is 52.

The spelling of 491444971531 in words is "four hundred ninety-one billion, four hundred forty-four million, nine hundred seventy-one thousand, five hundred thirty-one".