61660071 has 24 divisors (see below), whose sum is σ = 102879504. Its totient is φ = 35170560.

The previous prime is 61660069. The next prime is 61660097. The reversal of 61660071 is 17006616.

It is not a de Polignac number, because 61660071 - 2¹ = 61660069 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61660031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16636 + ... + 20001.

It is an arithmetic number, because the mean of its divisors is an integer number (4286646).

Almost surely, 2^61660071 is an apocalyptic number.

61660071 is a deficient number, since it is larger than the sum of its proper divisors (41219433).

61660071 is a wasteful number, since it uses less digits than its factorization.

61660071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36671 (or 36668 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 61660071 is about 7852.3926926765. The cubic root of 61660071 is about 395.0645004962.

Adding to 61660071 its reverse (17006616), we get a palindrome (78666687).

The spelling of 61660071 in words is "sixty-one million, six hundred sixty thousand, seventy-one".