640458624 has 192 divisors, whose sum is σ = 1881532800. Its totient is φ = 192890880.

The previous prime is 640458619. The next prime is 640458653. The reversal of 640458624 is 426854046.

It is a tau number, because it is divible by the number of its divisors (192).

It is a super-3 number, since 3×640458624³ (a number of 27 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4607547 + ... + 4607685.

It is an arithmetic number, because the mean of its divisors is an integer number (9799650).

Almost surely, 2^640458624 is an apocalyptic number.

640458624 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640458624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (940766400).

640458624 is an abundant number, since it is smaller than the sum of its proper divisors (1241074176).

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

640458624 is a wasteful number, since it uses less digits than its factorization.

640458624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253 (or 228 counting only the distinct ones).

The product of its (nonzero) digits is 184320, while the sum is 39.

The square root of 640458624 is about 25307.2840107349. The cubic root of 640458624 is about 861.9796759150.

The spelling of 640458624 in words is "six hundred forty million, four hundred fifty-eight thousand, six hundred twenty-four".