64685421 has 6 divisors (see below), whose sum is σ = 93434510. Its totient is φ = 43123608.

The previous prime is 64685393. The next prime is 64685429. The reversal of 64685421 is 12458646.

64685421 is a `hidden beast` number, since 646 + 8 + 5 + 4 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 40182921 + 24502500 = 6339^2 + 4950^2 .

It is not a de Polignac number, because 64685421 - 2⁵ = 64685389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64685429) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3593626 + ... + 3593643.

Almost surely, 2^64685421 is an apocalyptic number.

It is an amenable number.

64685421 is a deficient number, since it is larger than the sum of its proper divisors (28749089).

64685421 is a wasteful number, since it uses less digits than its factorization.

64685421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7187275 (or 7187272 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The square root of 64685421 is about 8042.7247248678. The cubic root of 64685421 is about 401.4228928548.

The spelling of 64685421 in words is "sixty-four million, six hundred eighty-five thousand, four hundred twenty-one".