61553440 has 96 divisors (see below), whose sum is σ = 158696496. Its totient is φ = 22425600.

The previous prime is 61553417. The next prime is 61553441. The reversal of 61553440 is 4435516.

61553440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 48274704 + 13278736 = 6948^2 + 3644^2 .

It is a junction number, because it is equal to n+sod(n) for n = 61553399 and 61553408.

It is not an unprimeable number, because it can be changed into a prime (61553441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 209934 + ... + 210226.

Almost surely, 2^61553440 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 61553440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79348248).

61553440 is an abundant number, since it is smaller than the sum of its proper divisors (97143056).

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

61553440 is a wasteful number, since it uses less digits than its factorization.

61553440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422 (or 414 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 61553440 is about 7845.6000407872. The cubic root of 61553440 is about 394.8366359650.

Adding to 61553440 its reverse (4435516), we get a palindrome (65988956).

The spelling of 61553440 in words is "sixty-one million, five hundred fifty-three thousand, four hundred forty".