645104340 has 144 divisors (see below), whose sum is σ = 2099260800. Its totient is φ = 159853824.

The previous prime is 645104329. The next prime is 645104351. The reversal of 645104340 is 43401546.

645104340 is a `hidden beast` number, since 645 + 10 + 4 + 3 + 4 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (645104329) and next prime (645104351).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 179481 + ... + 183039.

It is an arithmetic number, because the mean of its divisors is an integer number (14578200).

Almost surely, 2^645104340 is an apocalyptic number.

645104340 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 645104340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1049630400).

645104340 is an abundant number, since it is smaller than the sum of its proper divisors (1454156460).

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

645104340 is a wasteful number, since it uses less digits than its factorization.

645104340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3646 (or 3641 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 645104340 is about 25398.9043070759. The cubic root of 645104340 is about 864.0588469435.

Adding to 645104340 its reverse (43401546), we get a palindrome (688505886).

The spelling of 645104340 in words is "six hundred forty-five million, one hundred four thousand, three hundred forty".