61217280 has 120 divisors (see below), whose sum is σ = 212092452. Its totient is φ = 16318464.

The previous prime is 61217269. The next prime is 61217293. The reversal of 61217280 is 8271216.

It can be written as a sum of positive squares in 2 ways, for example, as 61214976 + 2304 = 7824^2 + 48^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21712 + ... + 24368.

Almost surely, 2^61217280 is an apocalyptic number.

61217280 is a gapful number since it is divisible by the number (60) 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 61217280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106046226).

61217280 is an abundant number, since it is smaller than the sum of its proper divisors (150875172).

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

61217280 is a wasteful number, since it uses less digits than its factorization.

61217280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2686 (or 2667 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 61217280 is about 7824.1472378784. The cubic root of 61217280 is about 394.1165535942.

Adding to 61217280 its reverse (8271216), we get a palindrome (69488496).

The spelling of 61217280 in words is "sixty-one million, two hundred seventeen thousand, two hundred eighty".