491701979 has 2 divisors, whose sum is σ = 491701980. Its totient is φ = 491701978.

The previous prime is 491701957. The next prime is 491701993. The reversal of 491701979 is 979107194.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 491701979 - 2¹² = 491697883 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (491701579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245850989 + 245850990.

It is an arithmetic number, because the mean of its divisors is an integer number (245850990).

Almost surely, 2^491701979 is an apocalyptic number.

491701979 is a deficient number, since it is larger than the sum of its proper divisors (1).

491701979 is an equidigital number, since it uses as much as digits as its factorization.

491701979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 142884, while the sum is 47.

The square root of 491701979 is about 22174.3540830393. The cubic root of 491701979 is about 789.2852473429.

The spelling of 491701979 in words is "four hundred ninety-one million, seven hundred one thousand, nine hundred seventy-nine".