64421220 has 24 divisors (see below), whose sum is σ = 180379584. Its totient is φ = 17178976.

The previous prime is 64421219. The next prime is 64421233. The reversal of 64421220 is 2212446.

It is an unprimeable number.

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, 536784 + ... + 536903.

It is an arithmetic number, because the mean of its divisors is an integer number (7515816).

Almost surely, 2^64421220 is an apocalyptic number.

64421220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

64421220 is an abundant number, since it is smaller than the sum of its proper divisors (115958364).

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

64421220 is a wasteful number, since it uses less digits than its factorization.

64421220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1073699 (or 1073697 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 64421220 is about 8026.2830749980. The cubic root of 64421220 is about 400.8756234768.

Adding to 64421220 its reverse (2212446), we get a palindrome (66633666).

The spelling of 64421220 in words is "sixty-four million, four hundred twenty-one thousand, two hundred twenty".