640172357760 has 256 divisors, whose sum is σ = 2222213616000. Its totient is φ = 155809775616.

The previous prime is 640172357719. The next prime is 640172357777. The reversal of 640172357760 is 67753271046.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2077351 + ... + 2365529.

Almost surely, 2^640172357760 is an apocalyptic number.

640172357760 is a gapful number since it is divisible by the number (60) 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 640172357760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1111106808000).

640172357760 is an abundant number, since it is smaller than the sum of its proper divisors (1582041258240).

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

640172357760 is a wasteful number, since it uses less digits than its factorization.

640172357760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288303 (or 288291 counting only the distinct ones).

The product of its (nonzero) digits is 1481760, while the sum is 48.

The spelling of 640172357760 in words is "six hundred forty billion, one hundred seventy-two million, three hundred fifty-seven thousand, seven hundred sixty".