61166661 has 16 divisors (see below), whose sum is σ = 83987904. Its totient is φ = 39567744.

The previous prime is 61166647. The next prime is 61166671. The reversal of 61166661 is 16666116.

It is not a de Polignac number, because 61166661 - 2¹⁷ = 61035589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61166621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70945 + ... + 71801.

It is an arithmetic number, because the mean of its divisors is an integer number (5249244).

Almost surely, 2^61166661 is an apocalyptic number.

It is an amenable number.

61166661 is a deficient number, since it is larger than the sum of its proper divisors (22821243).

61166661 is a wasteful number, since it uses less digits than its factorization.

61166661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1540.

The product of its digits is 7776, while the sum is 33.

The square root of 61166661 is about 7820.9117754901. The cubic root of 61166661 is about 394.0078953471.

The spelling of 61166661 in words is "sixty-one million, one hundred sixty-six thousand, six hundred sixty-one".