645154020 has 288 divisors, whose sum is σ = 2348236800. Its totient is φ = 140279040.

The previous prime is 645154019. The next prime is 645154021. The reversal of 645154020 is 20451546.

645154020 is a `hidden beast` number, since 645 + 15 + 4 + 0 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (645154019) and next prime (645154021).

It is not an unprimeable number, because it can be changed into a prime (645154021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3241881 + ... + 3242079.

It is an arithmetic number, because the mean of its divisors is an integer number (8153600).

Almost surely, 2^645154020 is an apocalyptic number.

645154020 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 645154020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1174118400).

645154020 is an abundant number, since it is smaller than the sum of its proper divisors (1703082780).

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

645154020 is a wasteful number, since it uses less digits than its factorization.

645154020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 335 (or 330 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 645154020 is about 25399.8822831918. The cubic root of 645154020 is about 864.0810269946.

The spelling of 645154020 in words is "six hundred forty-five million, one hundred fifty-four thousand, twenty".