61545665 has 4 divisors (see below), whose sum is σ = 73854804. Its totient is φ = 49236528.

The previous prime is 61545647. The next prime is 61545683. The reversal of 61545665 is 56654516.

61545665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (61545647) and next prime (61545683).

It can be written as a sum of positive squares in 2 ways, for example, as 12082576 + 49463089 = 3476^2 + 7033^2 .

It is a cyclic number.

It is not a de Polignac number, because 61545665 - 2⁸ = 61545409 is a prime.

It is a Duffinian 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 3 ways as a sum of consecutive naturals, for example, 6154562 + ... + 6154571.

It is an arithmetic number, because the mean of its divisors is an integer number (18463701).

Almost surely, 2^61545665 is an apocalyptic number.

It is an amenable number.

61545665 is a deficient number, since it is larger than the sum of its proper divisors (12309139).

61545665 is a wasteful number, since it uses less digits than its factorization.

61545665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12309138.

The product of its digits is 108000, while the sum is 38.

The square root of 61545665 is about 7845.1045244789. The cubic root of 61545665 is about 394.8200109309.

The spelling of 61545665 in words is "sixty-one million, five hundred forty-five thousand, six hundred sixty-five".