63681409 has 24 divisors (see below), whose sum is σ = 74145024. Its totient is φ = 54180000.

The previous prime is 63681389. The next prime is 63681413. The reversal of 63681409 is 90418636.

It is not a de Polignac number, because 63681409 - 2⁷ = 63681281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63681109) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 630459 + ... + 630559.

It is an arithmetic number, because the mean of its divisors is an integer number (3089376).

Almost surely, 2^63681409 is an apocalyptic number.

It is an amenable number.

63681409 is a deficient number, since it is larger than the sum of its proper divisors (10463615).

63681409 is a wasteful number, since it uses less digits than its factorization.

With its predecessor (63681408) it forms a Ruth-Aaron pair, since the sum of their prime factors is the same (229).

63681409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229 (or 186 counting only the distinct ones).

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

The square root of 63681409 is about 7980.0632203010. The cubic root of 63681409 is about 399.3351643461.

It can be divided in two parts, 6368 and 1409, that added together give a palindrome (7777).

The spelling of 63681409 in words is "sixty-three million, six hundred eighty-one thousand, four hundred nine".