645950 has 12 divisors (see below), whose sum is σ = 1201560. Its totient is φ = 258360.

The previous prime is 645941. The next prime is 645973. The reversal of 645950 is 59546.

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 6410 + ... + 6509.

It is an arithmetic number, because the mean of its divisors is an integer number (100130).

2⁶⁴⁵⁹⁵⁰ is an apocalyptic number.

645950 is a deficient number, since it is larger than the sum of its proper divisors (555610).

645950 is a wasteful number, since it uses less digits than its factorization.

645950 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12931 (or 12926 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 29.

The square root of 645950 is about 803.7101467569. The cubic root of 645950 is about 86.4436243747.

The spelling of 645950 in words is "six hundred forty-five thousand, nine hundred fifty".