661012166 has 16 divisors (see below), whose sum is σ = 1056283200. Its totient is φ = 309337128.

The previous prime is 661012133. The next prime is 661012169. The reversal of 661012166 is 661210166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661012169) 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 7 ways as a sum of consecutive naturals, for example, 101636 + ... + 107943.

It is an arithmetic number, because the mean of its divisors is an integer number (66017700).

Almost surely, 2^661012166 is an apocalyptic number.

661012166 is a deficient number, since it is larger than the sum of its proper divisors (395271034).

661012166 is a wasteful number, since it uses less digits than its factorization.

661012166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209683.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 661012166 is about 25710.1568645545. The cubic root of 661012166 is about 871.1036181557.

The spelling of 661012166 in words is "six hundred sixty-one million, twelve thousand, one hundred sixty-six".