64921600 has 84 divisors (see below), whose sum is σ = 161503614. Its totient is φ = 25886720.

The previous prime is 64921583. The next prime is 64921609. The reversal of 64921600 is 612946.

It can be written as a sum of positive squares in 3 ways, for example, as 31002624 + 33918976 = 5568^2 + 5824^2 .

It is not an unprimeable number, because it can be changed into a prime (64921609) 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, 204642 + ... + 204958.

Almost surely, 2^64921600 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 64921600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80751807).

64921600 is an abundant number, since it is smaller than the sum of its proper divisors (96582014).

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

64921600 is an equidigital number, since it uses as much as digits as its factorization.

64921600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 353 (or 324 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 64921600 is about 8057.3941196891. The cubic root of 64921600 is about 401.9108570276.

It can be divided in two parts, 64 and 921600, that multiplied together give a square (58982400 = 7680²).

The spelling of 64921600 in words is "sixty-four million, nine hundred twenty-one thousand, six hundred".