397213837 has 2 divisors, whose sum is σ = 397213838. Its totient is φ = 397213836.

The previous prime is 397213813. The next prime is 397213903. The reversal of 397213837 is 738312793.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 385179876 + 12033961 = 19626^2 + 3469^2 .

It is an emirp because it is prime and its reverse (738312793) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 397213837 - 2¹⁹ = 396689549 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 397213793 and 397213802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (397213237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198606918 + 198606919.

It is an arithmetic number, because the mean of its divisors is an integer number (198606919).

Almost surely, 2^397213837 is an apocalyptic number.

It is an amenable number.

397213837 is a deficient number, since it is larger than the sum of its proper divisors (1).

397213837 is an equidigital number, since it uses as much as digits as its factorization.

397213837 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 190512, while the sum is 43.

The square root of 397213837 is about 19930.2242084729. The cubic root of 397213837 is about 735.0915936265.

The spelling of 397213837 in words is "three hundred ninety-seven million, two hundred thirteen thousand, eight hundred thirty-seven".