390056861 has 2 divisors, whose sum is σ = 390056862. Its totient is φ = 390056860.

The previous prime is 390056809. The next prime is 390056879. The reversal of 390056861 is 168650093.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 199092100 + 190964761 = 14110^2 + 13819^2 .

It is an emirp because it is prime and its reverse (168650093) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 390056861 - 2²² = 385862557 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (390059861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195028430 + 195028431.

It is an arithmetic number, because the mean of its divisors is an integer number (195028431).

Almost surely, 2^390056861 is an apocalyptic number.

It is an amenable number.

390056861 is a deficient number, since it is larger than the sum of its proper divisors (1).

390056861 is an equidigital number, since it uses as much as digits as its factorization.

390056861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 390056861 is about 19749.8572399904. The cubic root of 390056861 is about 730.6498629141.

The spelling of 390056861 in words is "three hundred ninety million, fifty-six thousand, eight hundred sixty-one".