64519990 has 16 divisors (see below), whose sum is σ = 119882880. Its totient is φ = 24975360.

The previous prime is 64519969. The next prime is 64519993. The reversal of 64519990 is 9991546.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64519993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 103755 + ... + 104374.

It is an arithmetic number, because the mean of its divisors is an integer number (7492680).

Almost surely, 2^64519990 is an apocalyptic number.

64519990 is a deficient number, since it is larger than the sum of its proper divisors (55362890).

64519990 is a wasteful number, since it uses less digits than its factorization.

64519990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208167.

The product of its (nonzero) digits is 87480, while the sum is 43.

The square root of 64519990 is about 8032.4336287330. The cubic root of 64519990 is about 401.0803917569.

The spelling of 64519990 in words is "sixty-four million, five hundred nineteen thousand, nine hundred ninety".