397642213 has 4 divisors (see below), whose sum is σ = 397874988. Its totient is φ = 397409440.

The previous prime is 397642211. The next prime is 397642261. The reversal of 397642213 is 312246793.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 175244644 + 222397569 = 13238^2 + 14913^2 .

It is a cyclic number.

It is not a de Polignac number, because 397642213 - 2¹ = 397642211 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397642211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113806 + ... + 117247.

It is an arithmetic number, because the mean of its divisors is an integer number (99468747).

Almost surely, 2^397642213 is an apocalyptic number.

It is an amenable number.

397642213 is a deficient number, since it is larger than the sum of its proper divisors (232775).

397642213 is a wasteful number, since it uses less digits than its factorization.

397642213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232774.

The product of its digits is 54432, while the sum is 37.

The square root of 397642213 is about 19940.9682061830. The cubic root of 397642213 is about 735.3557523197.

The spelling of 397642213 in words is "three hundred ninety-seven million, six hundred forty-two thousand, two hundred thirteen".