65723440 has 40 divisors (see below), whose sum is σ = 153146448. Its totient is φ = 26231040.

The previous prime is 65723431. The next prime is 65723459. The reversal of 65723440 is 4432756.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 64374 + ... + 65386.

Almost surely, 2^65723440 is an apocalyptic number.

It is an amenable number.

65723440 is an abundant number, since it is smaller than the sum of its proper divisors (87423008).

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

65723440 is a wasteful number, since it uses less digits than its factorization.

65723440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1837 (or 1831 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 31.

The square root of 65723440 is about 8106.9994449241. Note that the first 3 decimals coincide. The cubic root of 65723440 is about 403.5587444484.

The spelling of 65723440 in words is "sixty-five million, seven hundred twenty-three thousand, four hundred forty".