645249024 has 192 divisors, whose sum is σ = 2185747200. Its totient is φ = 184246272.

The previous prime is 645249023. The next prime is 645249049. The reversal of 645249024 is 420942546.

645249024 is a `hidden beast` number, since 645 + 2 + 4 + 9 + 0 + 2 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

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

It is a self number, because there is not a number n which added to its sum of digits gives 645249024.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645249023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 386239 + ... + 387905.

It is an arithmetic number, because the mean of its divisors is an integer number (11384100).

Almost surely, 2^645249024 is an apocalyptic number.

645249024 is a gapful number since it is divisible by the number (64) 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 645249024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1092873600).

645249024 is an abundant number, since it is smaller than the sum of its proper divisors (1540498176).

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

645249024 is a wasteful number, since it uses less digits than its factorization.

645249024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1705 (or 1679 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 645249024 is about 25401.7523804953. The cubic root of 645249024 is about 864.1234391536.

The spelling of 645249024 in words is "six hundred forty-five million, two hundred forty-nine thousand, twenty-four".