61218280 has 16 divisors (see below), whose sum is σ = 137741220. Its totient is φ = 24487296.

The previous prime is 61218271. The next prime is 61218281. The reversal of 61218280 is 8281216.

It can be written as a sum of positive squares in 2 ways, for example, as 61183684 + 34596 = 7822^2 + 186^2 .

It is not an unprimeable number, because it can be changed into a prime (61218281) 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, 765189 + ... + 765268.

Almost surely, 2^61218280 is an apocalyptic number.

It is an amenable number.

61218280 is an abundant number, since it is smaller than the sum of its proper divisors (76522940).

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

61218280 is a wasteful number, since it uses less digits than its factorization.

61218280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1530468 (or 1530464 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 61218280 is about 7824.2111423453. The cubic root of 61218280 is about 394.1186995809.

Adding to 61218280 its reverse (8281216), we get a palindrome (69499496).

The spelling of 61218280 in words is "sixty-one million, two hundred eighteen thousand, two hundred eighty".