645059520 has 336 divisors, whose sum is σ = 2591409600. Its totient is φ = 147216384.

The previous prime is 645059489. The next prime is 645059521. The reversal of 645059520 is 25950546.

645059520 is a `hidden beast` number, since 6 + 45 + 0 + 595 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is a super-2 number, since 2×645059520² = 832203568685260800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645059521) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 987514 + ... + 988166.

Almost surely, 2^645059520 is an apocalyptic number.

645059520 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 645059520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1295704800).

645059520 is an abundant number, since it is smaller than the sum of its proper divisors (1946350080).

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

645059520 is a wasteful number, since it uses less digits than its factorization.

645059520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 697 (or 670 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 36.

The square root of 645059520 is about 25398.0219702244. The cubic root of 645059520 is about 864.0388357029.

The spelling of 645059520 in words is "six hundred forty-five million, fifty-nine thousand, five hundred twenty".