1640253888 has 672 divisors, whose sum is σ = 6420144640. Its totient is φ = 403107840.

The previous prime is 1640253887. The next prime is 1640253917. The reversal of 1640253888 is 8883520461.

It is a tau number, because it is divible by the number of its divisors (672).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640253883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 26889378 + ... + 26889438.

Almost surely, 2^1640253888 is an apocalyptic number.

1640253888 is a gapful number since it is divisible by the number (18) 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 1640253888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3210072320).

1640253888 is an abundant number, since it is smaller than the sum of its proper divisors (4779890752).

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

1640253888 is a wasteful number, since it uses less digits than its factorization.

1640253888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127 (or 105 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The square root of 1640253888 is about 40500.0479999716. The cubic root of 1640253888 is about 1179.3345592124.

The spelling of 1640253888 in words is "one billion, six hundred forty million, two hundred fifty-three thousand, eight hundred eighty-eight".