390216949 has 2 divisors, whose sum is σ = 390216950. Its totient is φ = 390216948.

The previous prime is 390216877. The next prime is 390216961. The reversal of 390216949 is 949612093.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 390062500 + 154449 = 19750^2 + 393^2 .

It is a cyclic number.

It is not a de Polignac number, because 390216949 - 2⁷ = 390216821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (390216979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195108474 + 195108475.

It is an arithmetic number, because the mean of its divisors is an integer number (195108475).

Almost surely, 2^390216949 is an apocalyptic number.

It is an amenable number.

390216949 is a deficient number, since it is larger than the sum of its proper divisors (1).

390216949 is an equidigital number, since it uses as much as digits as its factorization.

390216949 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 104976, while the sum is 43.

The square root of 390216949 is about 19753.9097142819. The cubic root of 390216949 is about 730.7498075534.

The spelling of 390216949 in words is "three hundred ninety million, two hundred sixteen thousand, nine hundred forty-nine".