66457865 has 8 divisors (see below), whose sum is σ = 79834248. Its totient is φ = 53109760.

The previous prime is 66457829. The next prime is 66457907. The reversal of 66457865 is 56875466.

It can be written as a sum of positive squares in 4 ways, for example, as 4032064 + 62425801 = 2008^2 + 7901^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66457865 - 2¹² = 66453769 is a prime.

It is a Duffinian number.

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, 1496 + ... + 11625.

It is an arithmetic number, because the mean of its divisors is an integer number (9979281).

Almost surely, 2^66457865 is an apocalyptic number.

It is an amenable number.

66457865 is a deficient number, since it is larger than the sum of its proper divisors (13376383).

66457865 is a wasteful number, since it uses less digits than its factorization.

66457865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14139.

The product of its digits is 1209600, while the sum is 47.

The square root of 66457865 is about 8152.1693431871. The cubic root of 66457865 is about 405.0563656753.

The spelling of 66457865 in words is "sixty-six million, four hundred fifty-seven thousand, eight hundred sixty-five".