61660072 has 8 divisors (see below), whose sum is σ = 115612650. Its totient is φ = 30830032.

The previous prime is 61660069. The next prime is 61660097. The reversal of 61660072 is 27006616.

It can be written as a sum of positive squares in only one way, i.e., 47416996 + 14243076 = 6886^2 + 3774^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 61660072.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3853747 + ... + 3853762.

Almost surely, 2^61660072 is an apocalyptic number.

It is an amenable number.

61660072 is a deficient number, since it is larger than the sum of its proper divisors (53952578).

61660072 is a wasteful number, since it uses less digits than its factorization.

61660072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7707515 (or 7707511 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 61660072 is about 7852.3927563514. The cubic root of 61660072 is about 395.0645026319.

Adding to 61660072 its reverse (27006616), we get a palindrome (88666688).

The spelling of 61660072 in words is "sixty-one million, six hundred sixty thousand, seventy-two".