351720 has 48 divisors (see below), whose sum is σ = 1144260. Its totient is φ = 93696.

The previous prime is 351707. The next prime is 351727. The reversal of 351720 is 27153.

It can be written as a sum of positive squares in 2 ways, for example, as 338724 + 12996 = 582^2 + 114^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 351693 and 351702.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 351720.

It is not an unprimeable number, because it can be changed into a prime (351727) by changing a digit.

351720 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 129 + ... + 848.

2³⁵¹⁷²⁰ is an apocalyptic number.

351720 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 351720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (572130).

351720 is an abundant number, since it is smaller than the sum of its proper divisors (792540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

351720 is a wasteful number, since it uses less digits than its factorization.

351720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 994 (or 987 counting only the distinct ones).

The product of its (nonzero) digits is 210, while the sum is 18.

The square root of 351720 is about 593.0598620713. The cubic root of 351720 is about 70.5882401961.

Adding to 351720 its reverse (27153), we get a palindrome (378873).

The spelling of 351720 in words is "three hundred fifty-one thousand, seven hundred twenty".