397213219861 has 2 divisors, whose sum is σ = 397213219862. Its totient is φ = 397213219860.

The previous prime is 397213219859. The next prime is 397213219877. The reversal of 397213219861 is 168912312793.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 391367852836 + 5845367025 = 625594^2 + 76455^2 .

It is a cyclic number.

It is not a de Polignac number, because 397213219861 - 2¹ = 397213219859 is a prime.

Together with 397213219859, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 397213219799 and 397213219808.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (397213219661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198606609930 + 198606609931.

It is an arithmetic number, because the mean of its divisors is an integer number (198606609931).

Almost surely, 2^397213219861 is an apocalyptic number.

It is an amenable number.

397213219861 is a deficient number, since it is larger than the sum of its proper divisors (1).

397213219861 is an equidigital number, since it uses as much as digits as its factorization.

397213219861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 979776, while the sum is 52.

It can be divided in two parts, 3972132 and 19861, that added together give a palindrome (3991993).

The spelling of 397213219861 in words is "three hundred ninety-seven billion, two hundred thirteen million, two hundred nineteen thousand, eight hundred sixty-one".