6421533264 has 60 divisors (see below), whose sum is σ = 18130458996. Its totient is φ = 2121563136.

The previous prime is 6421533253. The next prime is 6421533329. The reversal of 6421533264 is 4623351246.

6421533264 is a `hidden beast` number, since 64 + 2 + 1 + 533 + 2 + 64 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 2152217664 + 4269315600 = 46392^2 + 65340^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 181047 + ... + 213590.

Almost surely, 2^6421533264 is an apocalyptic number.

It is an amenable number.

6421533264 is an abundant number, since it is smaller than the sum of its proper divisors (11708925732).

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

6421533264 is a wasteful number, since it uses less digits than its factorization.

6421533264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394764 (or 394755 counting only the distinct ones).

The product of its digits is 103680, while the sum is 36.

The square root of 6421533264 is about 80134.4698865601. The cubic root of 6421533264 is about 1858.7154641132.

It can be divided in two parts, 64215 and 33264, that added together give a palindrome (97479).

The spelling of 6421533264 in words is "six billion, four hundred twenty-one million, five hundred thirty-three thousand, two hundred sixty-four".