351820813 has 4 divisors (see below), whose sum is σ = 352336608. Its totient is φ = 351305020.

The previous prime is 351820769. The next prime is 351820817. The reversal of 351820813 is 318028153.

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 an emirpimes, since its reverse is a distinct semiprime: 318028153 = 23 ⋅13827311.

It is a cyclic number.

It is not a de Polignac number, because 351820813 - 2²⁵ = 318266381 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (351820817) 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, 256873 + ... + 258238.

It is an arithmetic number, because the mean of its divisors is an integer number (88084152).

Almost surely, 2^351820813 is an apocalyptic number.

It is an amenable number.

351820813 is a deficient number, since it is larger than the sum of its proper divisors (515795).

351820813 is an equidigital number, since it uses as much as digits as its factorization.

351820813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515794.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 351820813 is about 18756.8870818161. The cubic root of 351820813 is about 705.9498375389.

Adding to 351820813 its reverse (318028153), we get a palindrome (669848966).

The spelling of 351820813 in words is "three hundred fifty-one million, eight hundred twenty thousand, eight hundred thirteen".