61631840 has 24 divisors (see below), whose sum is σ = 145605600. Its totient is φ = 24652672.

The previous prime is 61631837. The next prime is 61631849. The reversal of 61631840 is 4813616.

61631840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61631849) 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 3 ways as a sum of consecutive naturals, for example, 192440 + ... + 192759.

It is an arithmetic number, because the mean of its divisors is an integer number (6066900).

Almost surely, 2^61631840 is an apocalyptic number.

It is an amenable number.

61631840 is an abundant number, since it is smaller than the sum of its proper divisors (83973760).

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

61631840 is a wasteful number, since it uses less digits than its factorization.

61631840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 385214 (or 385206 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 61631840 is about 7850.5948819182. The cubic root of 61631840 is about 395.0041980006.

The spelling of 61631840 in words is "sixty-one million, six hundred thirty-one thousand, eight hundred forty".