63616681 has 8 divisors (see below), whose sum is σ = 65772800. Its totient is φ = 61467120.

The previous prime is 63616673. The next prime is 63616687. The reversal of 63616681 is 18661636.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 63616681 - 2³ = 63616673 is a prime.

It is a super-2 number, since 2×63616681² = 8094164202911522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 63616681.

It is not an unprimeable number, because it can be changed into a prime (63616687) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25435 + ... + 27823.

It is an arithmetic number, because the mean of its divisors is an integer number (8221600).

Almost surely, 2^63616681 is an apocalyptic number.

It is an amenable number.

63616681 is a deficient number, since it is larger than the sum of its proper divisors (2156119).

63616681 is a wasteful number, since it uses less digits than its factorization.

63616681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3279.

The product of its digits is 31104, while the sum is 37.

The square root of 63616681 is about 7976.0065822440. The cubic root of 63616681 is about 399.1998190937.

The spelling of 63616681 in words is "sixty-three million, six hundred sixteen thousand, six hundred eighty-one".