61857840 has 80 divisors (see below), whose sum is σ = 209200896. Its totient is φ = 14995200.

The previous prime is 61857839. The next prime is 61857847. The reversal of 61857840 is 4875816.

61857840 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 (80).

It is not an unprimeable number, because it can be changed into a prime (61857847) 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, 9076 + ... + 14355.

Almost surely, 2^61857840 is an apocalyptic number.

61857840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61857840 is an abundant number, since it is smaller than the sum of its proper divisors (147343056).

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

61857840 is a wasteful number, since it uses less digits than its factorization.

61857840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23458 (or 23452 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 39.

The square root of 61857840 is about 7864.9755244374. The cubic root of 61857840 is about 395.4864273891.

The spelling of 61857840 in words is "sixty-one million, eight hundred fifty-seven thousand, eight hundred forty".