640253846490 has 128 divisors (see below), whose sum is σ = 1667612344320. Its totient is φ = 156722807808.

The previous prime is 640253846483. The next prime is 640253846539. The reversal of 640253846490 is 94648352046.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3737659 + ... + 3905201.

It is an arithmetic number, because the mean of its divisors is an integer number (13028221440).

Almost surely, 2^640253846490 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640253846490, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (833806172160).

640253846490 is an abundant number, since it is smaller than the sum of its proper divisors (1027358497830).

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

640253846490 is a wasteful number, since it uses less digits than its factorization.

640253846490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167756.

The product of its (nonzero) digits is 4976640, while the sum is 51.

The spelling of 640253846490 in words is "six hundred forty billion, two hundred fifty-three million, eight hundred forty-six thousand, four hundred ninety".