396779857 has 2 divisors, whose sum is σ = 396779858. Its totient is φ = 396779856.

The previous prime is 396779849. The next prime is 396779863. The reversal of 396779857 is 758977693.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 388247616 + 8532241 = 19704^2 + 2921^2 .

It is a cyclic number.

It is not a de Polignac number, because 396779857 - 2³ = 396779849 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 396779795 and 396779804.

It is not a weakly prime, because it can be changed into another prime (396779057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198389928 + 198389929.

It is an arithmetic number, because the mean of its divisors is an integer number (198389929).

Almost surely, 2^396779857 is an apocalyptic number.

It is an amenable number.

396779857 is a deficient number, since it is larger than the sum of its proper divisors (1).

396779857 is an equidigital number, since it uses as much as digits as its factorization.

396779857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20003760, while the sum is 61.

The square root of 396779857 is about 19919.3337488983. Note that the first 3 decimals coincide. The cubic root of 396779857 is about 734.8237854825.

The spelling of 396779857 in words is "three hundred ninety-six million, seven hundred seventy-nine thousand, eight hundred fifty-seven".