61505388 has 144 divisors (see below), whose sum is σ = 192628800. Its totient is φ = 16482816.

The previous prime is 61505377. The next prime is 61505393. The reversal of 61505388 is 88350516.

61505388 is a `hidden beast` number, since 615 + 0 + 5 + 38 + 8 = 666.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 209770 + ... + 210062.

It is an arithmetic number, because the mean of its divisors is an integer number (1337700).

Almost surely, 2^61505388 is an apocalyptic number.

61505388 is a gapful number since it is divisible by the number (68) 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 61505388, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96314400).

61505388 is an abundant number, since it is smaller than the sum of its proper divisors (131123412).

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

61505388 is a wasteful number, since it uses less digits than its factorization.

61505388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341 (or 322 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The square root of 61505388 is about 7842.5370894883. The cubic root of 61505388 is about 394.7338654877.

The spelling of 61505388 in words is "sixty-one million, five hundred five thousand, three hundred eighty-eight".