645513000 has 256 divisors, whose sum is σ = 2271559680. Its totient is φ = 151200000.

The previous prime is 645512983. The next prime is 645513007. The reversal of 645513000 is 315546.

It is a super-4 number, since 4×645513000⁴ (a number of 36 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (645513007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1022685 + ... + 1023315.

It is an arithmetic number, because the mean of its divisors is an integer number (8873280).

Almost surely, 2^645513000 is an apocalyptic number.

645513000 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 645513000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1135779840).

645513000 is an abundant number, since it is smaller than the sum of its proper divisors (1626046680).

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

645513000 is a wasteful number, since it uses less digits than its factorization.

645513000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 697 (or 683 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 645513000 is about 25406.9478686441. The cubic root of 645513000 is about 864.2412627848.

Adding to 645513000 its reverse (315546), we get a palindrome (645828546).

The spelling of 645513000 in words is "six hundred forty-five million, five hundred thirteen thousand".