645414840 has 96 divisors (see below), whose sum is σ = 2397264480. Its totient is φ = 147522816.

The previous prime is 645414839. The next prime is 645414863. The reversal of 645414840 is 48414546.

It is a happy number.

645414840 is a `hidden beast` number, since 645 + 4 + 1 + 4 + 8 + 4 + 0 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 645414795 and 645414804.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 125539 + ... + 130578.

It is an arithmetic number, because the mean of its divisors is an integer number (24971505).

Almost surely, 2^645414840 is an apocalyptic number.

645414840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

645414840 is an abundant number, since it is smaller than the sum of its proper divisors (1751849640).

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

645414840 is a wasteful number, since it uses less digits than its factorization.

645414840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 256141 (or 256134 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 36.

The square root of 645414840 is about 25405.0160401445. The cubic root of 645414840 is about 864.1974535856.

The spelling of 645414840 in words is "six hundred forty-five million, four hundred fourteen thousand, eight hundred forty".