61755440 has 40 divisors (see below), whose sum is σ = 145021968. Its totient is φ = 24454400.

The previous prime is 61755433. The next prime is 61755461. The reversal of 61755440 is 4455716.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 61755397 and 61755406.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4259 + ... + 11901.

Almost surely, 2^61755440 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 61755440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72510984).

61755440 is an abundant number, since it is smaller than the sum of its proper divisors (83266528).

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

61755440 is a wasteful number, since it uses less digits than its factorization.

61755440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7757 (or 7751 counting only the distinct ones).

The product of its (nonzero) digits is 16800, while the sum is 32.

The square root of 61755440 is about 7858.4629540388. The cubic root of 61755440 is about 395.2680763143.

The spelling of 61755440 in words is "sixty-one million, seven hundred fifty-five thousand, four hundred forty".