64491520 has 104 divisors (see below), whose sum is σ = 160412544. Its totient is φ = 24870912.

The previous prime is 64491509. The next prime is 64491527. The reversal of 64491520 is 2519446.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (64491527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 962527 + ... + 962593.

Almost surely, 2^64491520 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 64491520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80206272).

64491520 is an abundant number, since it is smaller than the sum of its proper divisors (95921024).

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

64491520 is an equidigital number, since it uses as much as digits as its factorization.

64491520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143 (or 121 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 64491520 is about 8030.6612430111. The cubic root of 64491520 is about 401.0213896879.

The spelling of 64491520 in words is "sixty-four million, four hundred ninety-one thousand, five hundred twenty".