61667665 has 4 divisors (see below), whose sum is σ = 74001204. Its totient is φ = 49334128.

The previous prime is 61667591. The next prime is 61667701. The reversal of 61667665 is 56676616.

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

It can be written as a sum of positive squares in 2 ways, for example, as 39727809 + 21939856 = 6303^2 + 4684^2 .

It is a cyclic number.

It is not a de Polignac number, because 61667665 - 2¹⁵ = 61634897 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6166762 + ... + 6166771.

It is an arithmetic number, because the mean of its divisors is an integer number (18500301).

Almost surely, 2^61667665 is an apocalyptic number.

It is an amenable number.

61667665 is a deficient number, since it is larger than the sum of its proper divisors (12333539).

61667665 is a wasteful number, since it uses less digits than its factorization.

61667665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12333538.

The product of its digits is 272160, while the sum is 43.

The square root of 61667665 is about 7852.8762246708. The cubic root of 61667665 is about 395.0807184290.

It can be divided in two parts, 6166 and 7665, that added together give a palindrome (13831).

The spelling of 61667665 in words is "sixty-one million, six hundred sixty-seven thousand, six hundred sixty-five".