64099840 has 160 divisors (see below), whose sum is σ = 181684800. Its totient is φ = 21676032.

The previous prime is 64099829. The next prime is 64099859. The reversal of 64099840 is 4899046.

It is a tau number, because it is divible by the number of its divisors (160).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 64099793 and 64099802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 878044 + ... + 878116.

It is an arithmetic number, because the mean of its divisors is an integer number (1135530).

Almost surely, 2^64099840 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 64099840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90842400).

64099840 is an abundant number, since it is smaller than the sum of its proper divisors (117584960).

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

64099840 is an frugal number, since it uses more digits than its factorization.

64099840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117 (or 87 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 40.

The square root of 64099840 is about 8006.2375682964. The cubic root of 64099840 is about 400.2078919336.

The spelling of 64099840 in words is "sixty-four million, ninety-nine thousand, eight hundred forty".