397493861 has 4 divisors (see below), whose sum is σ = 397543692. Its totient is φ = 397444032.

The previous prime is 397493809. The next prime is 397493909. The reversal of 397493861 is 168394793.

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 237344836 + 160149025 = 15406^2 + 12655^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-397493861 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 (397496861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9956 + ... + 29901.

It is an arithmetic number, because the mean of its divisors is an integer number (99385923).

Almost surely, 2^397493861 is an apocalyptic number.

It is an amenable number.

397493861 is a deficient number, since it is larger than the sum of its proper divisors (49831).

397493861 is an equidigital number, since it uses as much as digits as its factorization.

397493861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49830.

The product of its digits is 979776, while the sum is 50.

The square root of 397493861 is about 19937.2480799131. The cubic root of 397493861 is about 735.2642923235.

The spelling of 397493861 in words is "three hundred ninety-seven million, four hundred ninety-three thousand, eight hundred sixty-one".