65447440 has 20 divisors (see below), whose sum is σ = 152165484. Its totient is φ = 26178944.

The previous prime is 65447411. The next prime is 65447441. The reversal of 65447440 is 4474456.

It can be written as a sum of positive squares in 2 ways, for example, as 48274704 + 17172736 = 6948^2 + 4144^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 65447396 and 65447405.

It is not an unprimeable number, because it can be changed into a prime (65447441) 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, 408967 + ... + 409126.

Almost surely, 2^65447440 is an apocalyptic number.

It is an amenable number.

65447440 is an abundant number, since it is smaller than the sum of its proper divisors (86718044).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65447440 is a wasteful number, since it uses less digits than its factorization.

65447440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 818106 (or 818100 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 34.

The square root of 65447440 is about 8089.9592087970. The cubic root of 65447440 is about 402.9930482949.

The spelling of 65447440 in words is "sixty-five million, four hundred forty-seven thousand, four hundred forty".