645415344 has 160 divisors (see below), whose sum is σ = 2157719040. Its totient is φ = 180880128.

The previous prime is 645415339. The next prime is 645415349. The reversal of 645415344 is 443514546.

645415344 is a `hidden beast` number, since 64 + 541 + 53 + 4 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (645415339) and next prime (645415349).

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 = 645415299 and 645415308.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645415349) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 158259 + ... + 162285.

It is an arithmetic number, because the mean of its divisors is an integer number (13485744).

Almost surely, 2^645415344 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645415344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1078859520).

645415344 is an abundant number, since it is smaller than the sum of its proper divisors (1512303696).

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

645415344 is a wasteful number, since it uses less digits than its factorization.

645415344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4104 (or 4092 counting only the distinct ones).

The product of its digits is 115200, while the sum is 36.

The square root of 645415344 is about 25405.0259594435. The cubic root of 645415344 is about 864.1976785342.

The spelling of 645415344 in words is "six hundred forty-five million, four hundred fifteen thousand, three hundred forty-four".