361878561 has 12 divisors (see below), whose sum is σ = 570233040. Its totient is φ = 219320280.

The previous prime is 361878557. The next prime is 361878571. The reversal of 361878561 is 165878163.

361878561 is a `hidden beast` number, since 3 + 6 + 1 + 87 + 8 + 561 = 666.

It is not a de Polignac number, because 361878561 - 2² = 361878557 is a prime.

It is a super-2 number, since 2×361878561² = 261912185822861442, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (361878511) 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, 1827571 + ... + 1827768.

It is an arithmetic number, because the mean of its divisors is an integer number (47519420).

Almost surely, 2^361878561 is an apocalyptic number.

It is an amenable number.

361878561 is a deficient number, since it is larger than the sum of its proper divisors (208354479).

361878561 is a wasteful number, since it uses less digits than its factorization.

361878561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3655356 (or 3655353 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 361878561 is about 19023.1059766800. The cubic root of 361878561 is about 712.6138927813.

The spelling of 361878561 in words is "three hundred sixty-one million, eight hundred seventy-eight thousand, five hundred sixty-one".