64519390720 has 80 divisors (see below), whose sum is σ = 156141733968. Its totient is φ = 25566453760.

The previous prime is 64519390693. The next prime is 64519390751. The reversal of 64519390720 is 2709391546.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 156150 + ... + 391690.

Almost surely, 2^64519390720 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 64519390720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78070866984).

64519390720 is an abundant number, since it is smaller than the sum of its proper divisors (91622343248).

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

64519390720 is a wasteful number, since it uses less digits than its factorization.

64519390720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235671 (or 235655 counting only the distinct ones).

The product of its (nonzero) digits is 408240, while the sum is 46.

The spelling of 64519390720 in words is "sixty-four billion, five hundred nineteen million, three hundred ninety thousand, seven hundred twenty".