61660161 has 6 divisors (see below), whose sum is σ = 89064690. Its totient is φ = 41106768.

The previous prime is 61660127. The next prime is 61660189. The reversal of 61660161 is 16106616.

It can be written as a sum of positive squares in only one way, i.e., 35034561 + 26625600 = 5919^2 + 5160^2 .

It is not a de Polignac number, because 61660161 - 2⁶ = 61660097 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61661161) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3425556 + ... + 3425573.

It is an arithmetic number, because the mean of its divisors is an integer number (14844115).

Almost surely, 2^61660161 is an apocalyptic number.

It is an amenable number.

61660161 is a deficient number, since it is larger than the sum of its proper divisors (27404529).

61660161 is a wasteful number, since it uses less digits than its factorization.

61660161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6851135 (or 6851132 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 61660161 is about 7852.3984234118. The cubic root of 61660161 is about 395.0646927102.

Adding to 61660161 its reverse (16106616), we get a palindrome (77766777).

The spelling of 61660161 in words is "sixty-one million, six hundred sixty thousand, one hundred sixty-one".