65638749 has 48 divisors (see below), whose sum is σ = 104867840. Its totient is φ = 36352800.

The previous prime is 65638733. The next prime is 65638813. The reversal of 65638749 is 94783656.

It is not a de Polignac number, because 65638749 - 2⁴ = 65638733 is a prime.

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

It is a junction number, because it is equal to n+sod(n) for n = 65638698 and 65638707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65638709) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 213654 + ... + 213960.

Almost surely, 2^65638749 is an apocalyptic number.

It is an amenable number.

65638749 is a deficient number, since it is larger than the sum of its proper divisors (39229091).

65638749 is a wasteful number, since it uses less digits than its factorization.

65638749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382 (or 371 counting only the distinct ones).

The product of its digits is 1088640, while the sum is 48.

The square root of 65638749 is about 8101.7744352703. The cubic root of 65638749 is about 403.3853284667.

The spelling of 65638749 in words is "sixty-five million, six hundred thirty-eight thousand, seven hundred forty-nine".