640033397280 has 240 divisors, whose sum is σ = 2262232032984. Its totient is φ = 170415083520.

The previous prime is 640033397257. The next prime is 640033397281. The reversal of 640033397280 is 82793330046.

It can be written as a sum of positive squares in 4 ways, for example, as 639929601936 + 103795344 = 799956^2 + 10188^2 .

It is a tau number, because it is divible by the number of its divisors (240).

It is a super-2 number, since 2×640033397280² (a number of 24 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (640033397281) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 8529204 + ... + 8603916.

Almost surely, 2^640033397280 is an apocalyptic number.

640033397280 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 640033397280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1131116016492).

640033397280 is an abundant number, since it is smaller than the sum of its proper divisors (1622198635704).

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

640033397280 is a wasteful number, since it uses less digits than its factorization.

640033397280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75401 (or 75384 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 45.

The spelling of 640033397280 in words is "six hundred forty billion, thirty-three million, three hundred ninety-seven thousand, two hundred eighty".