61785840 has 80 divisors (see below), whose sum is σ = 196023168. Its totient is φ = 16090368.

The previous prime is 61785817. The next prime is 61785851. The reversal of 61785840 is 4858716.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7327 + ... + 13313.

Almost surely, 2^61785840 is an apocalyptic number.

61785840 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 61785840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98011584).

61785840 is an abundant number, since it is smaller than the sum of its proper divisors (134237328).

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

61785840 is a wasteful number, since it uses less digits than its factorization.

61785840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6046 (or 6040 counting only the distinct ones).

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

The square root of 61785840 is about 7860.3969365421. The cubic root of 61785840 is about 395.3329244656.

The spelling of 61785840 in words is "sixty-one million, seven hundred eighty-five thousand, eight hundred forty".