247449840 has 120 divisors (see below), whose sum is σ = 843268944. Its totient is φ = 59980800.

The previous prime is 247449833. The next prime is 247449857. The reversal of 247449840 is 48944742.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×247449840² = 122462846632051200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 247449792 and 247449801.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24780 + ... + 33300.

Almost surely, 2^247449840 is an apocalyptic number.

247449840 is a gapful number since it is divisible by the number (20) 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 247449840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (421634472).

247449840 is an abundant number, since it is smaller than the sum of its proper divisors (595819104).

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

247449840 is a wasteful number, since it uses less digits than its factorization.

247449840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8559 (or 8542 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 42.

The square root of 247449840 is about 15730.5384523226. The cubic root of 247449840 is about 627.8111999563.

The spelling of 247449840 in words is "two hundred forty-seven million, four hundred forty-nine thousand, eight hundred forty".