823861397 has 4 divisors (see below), whose sum is σ = 823928160. Its totient is φ = 823794636.

The previous prime is 823861391. The next prime is 823861399. The reversal of 823861397 is 793168328.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 823861397 - 2⁶ = 823861333 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 (823861391) 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, 8873 + ... + 41550.

It is an arithmetic number, because the mean of its divisors is an integer number (205982040).

Almost surely, 2^823861397 is an apocalyptic number.

It is an amenable number.

823861397 is a deficient number, since it is larger than the sum of its proper divisors (66763).

823861397 is a wasteful number, since it uses less digits than its factorization.

823861397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66762.

The product of its digits is 435456, while the sum is 47.

The square root of 823861397 is about 28702.9858551336. The cubic root of 823861397 is about 937.4570611919.

The spelling of 823861397 in words is "eight hundred twenty-three million, eight hundred sixty-one thousand, three hundred ninety-seven".