61691328 has 112 divisors (see below), whose sum is σ = 191008000. Its totient is φ = 19471104.

The previous prime is 61691299. The next prime is 61691363. The reversal of 61691328 is 82319616.

61691328 is a `hidden beast` number, since 616 + 9 + 1 + 32 + 8 = 666.

61691328 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 61691292 and 61691301.

It is a congruent number.

It is an unprimeable number.

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, 31893 + ... + 33771.

Almost surely, 2^61691328 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 61691328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95504000).

61691328 is an abundant number, since it is smaller than the sum of its proper divisors (129316672).

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

61691328 is a wasteful number, since it uses less digits than its factorization.

61691328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1919 (or 1903 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 61691328 is about 7854.3827255870. The cubic root of 61691328 is about 395.1312451760.

The spelling of 61691328 in words is "sixty-one million, six hundred ninety-one thousand, three hundred twenty-eight".