640054144 has 16 divisors (see below), whose sum is σ = 1275108120. Its totient is φ = 320027008.

The previous prime is 640054133. The next prime is 640054147. The reversal of 640054144 is 441450046.

It is a tau number, because it is divible by the number of its divisors (16).

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640054147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2500084 + ... + 2500339.

Almost surely, 2^640054144 is an apocalyptic number.

640054144 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

640054144 is a deficient number, since it is larger than the sum of its proper divisors (635053976).

640054144 is an equidigital number, since it uses as much as digits as its factorization.

640054144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5000437 (or 5000425 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 28.

The square root of 640054144 is about 25299.2913734753. The cubic root of 640054144 is about 861.7981773508.

The spelling of 640054144 in words is "six hundred forty million, fifty-four thousand, one hundred forty-four".