63659961 has 6 divisors (see below), whose sum is σ = 91953290. Its totient is φ = 42439968.

The previous prime is 63659903. The next prime is 63659963. The reversal of 63659961 is 16995636.

63659961 is a `hidden beast` number, since 636 + 5 + 9 + 9 + 6 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 44475561 + 19184400 = 6669^2 + 4380^2 .

It is not a de Polignac number, because 63659961 - 2¹⁴ = 63643577 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63659963) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3536656 + ... + 3536673.

Almost surely, 2^63659961 is an apocalyptic number.

It is an amenable number.

63659961 is a deficient number, since it is larger than the sum of its proper divisors (28293329).

63659961 is a wasteful number, since it uses less digits than its factorization.

63659961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7073335 (or 7073332 counting only the distinct ones).

The product of its digits is 262440, while the sum is 45.

The square root of 63659961 is about 7978.7192581266. The cubic root of 63659961 is about 399.2903270721.

It can be divided in two parts, 63659 and 961, that added together give a triangular number (64620 = T₃₅₉).

The spelling of 63659961 in words is "sixty-three million, six hundred fifty-nine thousand, nine hundred sixty-one".