61665554 has 8 divisors (see below), whose sum is σ = 92719308. Its totient is φ = 30759120.

The previous prime is 61665533. The next prime is 61665557. The reversal of 61665554 is 45556616.

61665554 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 53684929 + 7980625 = 7327^2 + 2825^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (61665557) 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 in 3 ways as a sum of consecutive naturals, for example, 35777 + ... + 37460.

Almost surely, 2^61665554 is an apocalyptic number.

61665554 is a deficient number, since it is larger than the sum of its proper divisors (31053754).

61665554 is a wasteful number, since it uses less digits than its factorization.

61665554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73660.

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

The square root of 61665554 is about 7852.7418141691. The cubic root of 61665554 is about 395.0762102592.

The spelling of 61665554 in words is "sixty-one million, six hundred sixty-five thousand, five hundred fifty-four".