64869984 has 120 divisors (see below), whose sum is σ = 197588160. Its totient is φ = 20853504.

The previous prime is 64869979. The next prime is 64869989. The reversal of 64869984 is 48996846.

It is an interprime number because it is at equal distance from previous prime (64869979) and next prime (64869989).

It is a super-2 number, since 2×64869984² = 8416229648320512, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 64869984.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64869989) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 74737 + ... + 75599.

It is an arithmetic number, because the mean of its divisors is an integer number (1646568).

Almost surely, 2^64869984 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64869984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98794080).

64869984 is an abundant number, since it is smaller than the sum of its proper divisors (132718176).

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

64869984 is a wasteful number, since it uses less digits than its factorization.

64869984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 914 (or 897 counting only the distinct ones).

The product of its digits is 2985984, while the sum is 54.

The square root of 64869984 is about 8054.1904621135. The cubic root of 64869984 is about 401.8043155426.

The spelling of 64869984 in words is "sixty-four million, eight hundred sixty-nine thousand, nine hundred eighty-four".