61505865 has 16 divisors (see below), whose sum is σ = 109344000. Its totient is φ = 32803056.

The previous prime is 61505837. The next prime is 61505879. The reversal of 61505865 is 56850516.

It is not a de Polignac number, because 61505865 - 2⁵ = 61505833 is a prime.

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 15 ways as a sum of consecutive naturals, for example, 227665 + ... + 227934.

It is an arithmetic number, because the mean of its divisors is an integer number (6834000).

Almost surely, 2^61505865 is an apocalyptic number.

It is an amenable number.

61505865 is a deficient number, since it is larger than the sum of its proper divisors (47838135).

61505865 is a wasteful number, since it uses less digits than its factorization.

61505865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 455613 (or 455607 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 36.

The square root of 61505865 is about 7842.5675005065. The cubic root of 61505865 is about 394.7348859271.

The spelling of 61505865 in words is "sixty-one million, five hundred five thousand, eight hundred sixty-five".