64821405 has 16 divisors (see below), whose sum is σ = 113143104. Its totient is φ = 31428480.

The previous prime is 64821401. The next prime is 64821437. The reversal of 64821405 is 50412846.

It is not a de Polignac number, because 64821405 - 2² = 64821401 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64821401) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 196264 + ... + 196593.

It is an arithmetic number, because the mean of its divisors is an integer number (7071444).

Almost surely, 2^64821405 is an apocalyptic number.

It is an amenable number.

64821405 is a deficient number, since it is larger than the sum of its proper divisors (48321699).

64821405 is a wasteful number, since it uses less digits than its factorization.

64821405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392876.

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 64821405 is about 8051.1741379752. The cubic root of 64821405 is about 401.7039911444.

It can be divided in two parts, 6482 and 1405, that added together give a palindrome (7887).

The spelling of 64821405 in words is "sixty-four million, eight hundred twenty-one thousand, four hundred five".