494078821 has 2 divisors, whose sum is σ = 494078822. Its totient is φ = 494078820.

The previous prime is 494078791. The next prime is 494078861. The reversal of 494078821 is 128870494.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 486864225 + 7214596 = 22065^2 + 2686^2 .

It is a cyclic number.

It is not a de Polignac number, because 494078821 - 2⁵ = 494078789 is a prime.

It is a super-2 number, since 2×494078821² = 488227762721500082, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (494078861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 247039410 + 247039411.

It is an arithmetic number, because the mean of its divisors is an integer number (247039411).

Almost surely, 2^494078821 is an apocalyptic number.

It is an amenable number.

494078821 is a deficient number, since it is larger than the sum of its proper divisors (1).

494078821 is an equidigital number, since it uses as much as digits as its factorization.

494078821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 129024, while the sum is 43.

The square root of 494078821 is about 22227.8838623923. The cubic root of 494078821 is about 790.5549809645.

The spelling of 494078821 in words is "four hundred ninety-four million, seventy-eight thousand, eight hundred twenty-one".