661142986 has 24 divisors (see below), whose sum is σ = 1193412420. Its totient is φ = 273575232.

The previous prime is 661142959. The next prime is 661142987. The reversal of 661142986 is 689241166.

It can be written as a sum of positive squares in 2 ways, for example, as 608855625 + 52287361 = 24675^2 + 7231^2 .

It is a super-2 number, since 2×661142986² = 874220095873992392, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (661142987) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 113475 + ... + 119158.

Almost surely, 2^661142986 is an apocalyptic number.

661142986 is a deficient number, since it is larger than the sum of its proper divisors (532269434).

661142986 is a wasteful number, since it uses less digits than its factorization.

661142986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232678 (or 232671 counting only the distinct ones).

The product of its digits is 124416, while the sum is 43.

The square root of 661142986 is about 25712.7008694147. The cubic root of 661142986 is about 871.1610806676.

The spelling of 661142986 in words is "six hundred sixty-one million, one hundred forty-two thousand, nine hundred eighty-six".