661016061 has 12 divisors (see below), whose sum is σ = 1005053920. Its totient is φ = 417483720.

The previous prime is 661016017. The next prime is 661016087. The reversal of 661016061 is 160610166.

It is not a de Polignac number, because 661016061 - 2¹⁵ = 660983293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661016011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1932625 + ... + 1932966.

Almost surely, 2^661016061 is an apocalyptic number.

It is an amenable number.

661016061 is a deficient number, since it is larger than the sum of its proper divisors (344037859).

661016061 is a wasteful number, since it uses less digits than its factorization.

661016061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3865616 (or 3865613 counting only the distinct ones).

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

The square root of 661016061 is about 25710.2326127167. The cubic root of 661016061 is about 871.1053291388.

The spelling of 661016061 in words is "six hundred sixty-one million, sixteen thousand, sixty-one".