64649538 has 48 divisors (see below), whose sum is σ = 151960536. Its totient is φ = 19783680.

The previous prime is 64649503. The next prime is 64649551. The reversal of 64649538 is 83594646.

It can be written as a sum of positive squares in 4 ways, for example, as 51883209 + 12766329 = 7203^2 + 3573^2 .

It is a super-2 number, since 2×64649538² = 8359125527226888, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 64649493 and 64649502.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9970 + ... + 15122.

Almost surely, 2^64649538 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64649538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75980268).

64649538 is an abundant number, since it is smaller than the sum of its proper divisors (87310998).

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

64649538 is a wasteful number, since it uses less digits than its factorization.

64649538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5219 (or 5216 counting only the distinct ones).

The product of its digits is 622080, while the sum is 45.

The square root of 64649538 is about 8040.4936415621. The cubic root of 64649538 is about 401.3486519013.

The spelling of 64649538 in words is "sixty-four million, six hundred forty-nine thousand, five hundred thirty-eight".