351221440 has 56 divisors (see below), whose sum is σ = 844704432. Its totient is φ = 139084800.

The previous prime is 351221419. The next prime is 351221461. The reversal of 351221440 is 44122153.

It is an interprime number because it is at equal distance from previous prime (351221419) and next prime (351221461).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26887 + ... + 37753.

Almost surely, 2^351221440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 351221440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (422352216).

351221440 is an abundant number, since it is smaller than the sum of its proper divisors (493482992).

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

351221440 is a wasteful number, since it uses less digits than its factorization.

351221440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10985 (or 10975 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 351221440 is about 18740.9028597877. The cubic root of 351221440 is about 705.5487168848.

Adding to 351221440 its reverse (44122153), we get a palindrome (395343593).

The spelling of 351221440 in words is "three hundred fifty-one million, two hundred twenty-one thousand, four hundred forty".