61605857 has 2 divisors, whose sum is σ = 61605858. Its totient is φ = 61605856.

The previous prime is 61605839. The next prime is 61605877. The reversal of 61605857 is 75850616.

It is a happy number.

61605857 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60824401 + 781456 = 7799^2 + 884^2 .

It is a cyclic number.

It is not a de Polignac number, because 61605857 - 2¹⁶ = 61540321 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61605857.

It is not a weakly prime, because it can be changed into another prime (61605827) 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 as a sum of consecutive naturals, namely, 30802928 + 30802929.

It is an arithmetic number, because the mean of its divisors is an integer number (30802929).

Almost surely, 2^61605857 is an apocalyptic number.

It is an amenable number.

61605857 is a deficient number, since it is larger than the sum of its proper divisors (1).

61605857 is an equidigital number, since it uses as much as digits as its factorization.

61605857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 50400, while the sum is 38.

The square root of 61605857 is about 7848.9398647206. The cubic root of 61605857 is about 394.9486810432.

The spelling of 61605857 in words is "sixty-one million, six hundred five thousand, eight hundred fifty-seven".