65239440 has 80 divisors (see below), whose sum is σ = 231139968. Its totient is φ = 14911488.

The previous prime is 65239429. The next prime is 65239451. The reversal of 65239440 is 4493256.

It is an interprime number because it is at equal distance from previous prime (65239429) and next prime (65239451).

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17737 + ... + 21096.

Almost surely, 2^65239440 is an apocalyptic number.

65239440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

65239440 is an abundant number, since it is smaller than the sum of its proper divisors (165900528).

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

65239440 is a wasteful number, since it uses less digits than its factorization.

65239440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38856 (or 38850 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 33.

The square root of 65239440 is about 8077.0935366628. The cubic root of 65239440 is about 402.5656747637.

The spelling of 65239440 in words is "sixty-five million, two hundred thirty-nine thousand, four hundred forty".