64400000 has 192 divisors, whose sum is σ = 191237760. Its totient is φ = 21120000.

The previous prime is 64399999. The next prime is 64400009. The reversal of 64400000 is 446.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a nialpdrome in base 10.

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64400009) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2799989 + ... + 2800011.

It is an arithmetic number, because the mean of its divisors is an integer number (996030).

Almost surely, 2^64400000 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 64400000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95618880).

64400000 is an abundant number, since it is smaller than the sum of its proper divisors (126837760).

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

64400000 is an frugal number, since it uses more digits than its factorization.

64400000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69 (or 37 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 64400000 is about 8024.9610590956. The cubic root of 64400000 is about 400.8316032254.

Adding to 64400000 its reverse (446), we get a palindrome (64400446).

The spelling of 64400000 in words is "sixty-four million, four hundred thousand".