64351728 has 60 divisors (see below), whose sum is σ = 205826608. Its totient is φ = 18385920.

The previous prime is 64351711. The next prime is 64351733. The reversal of 64351728 is 82715346.

64351728 is a `hidden beast` number, since 643 + 5 + 1 + 7 + 2 + 8 = 666.

It is a super-2 number, since 2×64351728² = 8282289793171968, which contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 64351692 and 64351701.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 30913 + ... + 32928.

Almost surely, 2^64351728 is an apocalyptic number.

It is an amenable number.

64351728 is an abundant number, since it is smaller than the sum of its proper divisors (141474880).

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

64351728 is a wasteful number, since it uses less digits than its factorization.

64351728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63862 (or 63853 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 64351728 is about 8021.9528794428. The cubic root of 64351728 is about 400.7314283828.

It can be divided in two parts, 643517 and 28, that added together give a triangular number (643545 = T₁₁₃₄).

The spelling of 64351728 in words is "sixty-four million, three hundred fifty-one thousand, seven hundred twenty-eight".