65449681 has 4 divisors (see below), whose sum is σ = 71399664. Its totient is φ = 59499700.

The previous prime is 65449673. The next prime is 65449729. The reversal of 65449681 is 18694456.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 65449681 - 2³ = 65449673 is a prime.

It is a super-2 number, since 2×65449681² = 8567321486003522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65419681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2974975 + ... + 2974996.

It is an arithmetic number, because the mean of its divisors is an integer number (17849916).

Almost surely, 2^65449681 is an apocalyptic number.

It is an amenable number.

65449681 is a deficient number, since it is larger than the sum of its proper divisors (5949983).

65449681 is a wasteful number, since it uses less digits than its factorization.

65449681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5949982.

The product of its digits is 207360, while the sum is 43.

The square root of 65449681 is about 8090.0977126361. The cubic root of 65449681 is about 402.9976478999.

The spelling of 65449681 in words is "sixty-five million, four hundred forty-nine thousand, six hundred eighty-one".