638789265 has 12 divisors (see below), whose sum is σ = 1107234804. Its totient is φ = 340687584.

The previous prime is 638789237. The next prime is 638789269. The reversal of 638789265 is 562987836.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 459845136 + 178944129 = 21444^2 + 13377^2 .

It is not a de Polignac number, because 638789265 - 2²¹ = 636692113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (638789269) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7097614 + ... + 7097703.

It is an arithmetic number, because the mean of its divisors is an integer number (92269567).

Almost surely, 2^638789265 is an apocalyptic number.

It is an amenable number.

638789265 is a deficient number, since it is larger than the sum of its proper divisors (468445539).

638789265 is a wasteful number, since it uses less digits than its factorization.

638789265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14195328 (or 14195325 counting only the distinct ones).

The product of its digits is 4354560, while the sum is 54.

The square root of 638789265 is about 25274.2807019310. The cubic root of 638789265 is about 861.2301059960.

The spelling of 638789265 in words is "six hundred thirty-eight million, seven hundred eighty-nine thousand, two hundred sixty-five".