645441774 has 32 divisors (see below), whose sum is σ = 1307040000. Its totient is φ = 212471424.

The previous prime is 645441773. The next prime is 645441787. The reversal of 645441774 is 477144546.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645441773) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 164022 + ... + 167910.

It is an arithmetic number, because the mean of its divisors is an integer number (40845000).

Almost surely, 2^645441774 is an apocalyptic number.

645441774 is an abundant number, since it is smaller than the sum of its proper divisors (661598226).

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

645441774 is a wasteful number, since it uses less digits than its factorization.

645441774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4232.

The product of its digits is 376320, while the sum is 42.

The square root of 645441774 is about 25405.5461267811. The cubic root of 645441774 is about 864.2094747794.

The spelling of 645441774 in words is "six hundred forty-five million, four hundred forty-one thousand, seven hundred seventy-four".