61666544 has 10 divisors (see below), whose sum is σ = 119478960. Its totient is φ = 30833264.

The previous prime is 61666543. The next prime is 61666559. The reversal of 61666544 is 44566616.

It is a junction number, because it is equal to n+sod(n) for n = 61666498 and 61666507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61666543) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1927064 + ... + 1927095.

It is an arithmetic number, because the mean of its divisors is an integer number (11947896).

Almost surely, 2^61666544 is an apocalyptic number.

It is an amenable number.

61666544 is a deficient number, since it is larger than the sum of its proper divisors (57812416).

61666544 is a wasteful number, since it uses less digits than its factorization.

61666544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3854167 (or 3854161 counting only the distinct ones).

The product of its digits is 103680, while the sum is 38.

The square root of 61666544 is about 7852.8048492243. The cubic root of 61666544 is about 395.0783244776.

The spelling of 61666544 in words is "sixty-one million, six hundred sixty-six thousand, five hundred forty-four".