61878240 has 144 divisors (see below), whose sum is σ = 213817968. Its totient is φ = 16293888.

The previous prime is 61878227. The next prime is 61878241. The reversal of 61878240 is 4287816.

61878240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 61878195 and 61878204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61878241) 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 23 ways as a sum of consecutive naturals, for example, 139459 + ... + 139901.

It is an arithmetic number, because the mean of its divisors is an integer number (1484847).

Almost surely, 2^61878240 is an apocalyptic number.

61878240 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 61878240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106908984).

61878240 is an abundant number, since it is smaller than the sum of its proper divisors (151939728).

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

61878240 is a wasteful number, since it uses less digits than its factorization.

61878240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 561 (or 550 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 61878240 is about 7866.2723064994. The cubic root of 61878240 is about 395.5298982269.

The spelling of 61878240 in words is "sixty-one million, eight hundred seventy-eight thousand, two hundred forty".