645739248 has 180 divisors, whose sum is σ = 2133899880. Its totient is φ = 167650560.

The previous prime is 645739231. The next prime is 645739261. The reversal of 645739248 is 842937546.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a junction number, because it is equal to n+sod(n) for n = 645739197 and 645739206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 283458 + ... + 285726.

Almost surely, 2^645739248 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 645739248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1066949940).

645739248 is an abundant number, since it is smaller than the sum of its proper divisors (1488160632).

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

645739248 is a wasteful number, since it uses less digits than its factorization.

645739248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2316 (or 2292 counting only the distinct ones).

The product of its digits is 1451520, while the sum is 48.

The square root of 645739248 is about 25411.3999614346. The cubic root of 645739248 is about 864.3422212563.

The spelling of 645739248 in words is "six hundred forty-five million, seven hundred thirty-nine thousand, two hundred forty-eight".