645442055 has 16 divisors (see below), whose sum is σ = 779756544. Its totient is φ = 512883360.

The previous prime is 645442051. The next prime is 645442079. The reversal of 645442055 is 550244546.

It is not a de Polignac number, because 645442055 - 2² = 645442051 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645442051) 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, 681092 + ... + 682038.

It is an arithmetic number, because the mean of its divisors is an integer number (48734784).

Almost surely, 2^645442055 is an apocalyptic number.

645442055 is a deficient number, since it is larger than the sum of its proper divisors (134314489).

645442055 is a wasteful number, since it uses less digits than its factorization.

645442055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1726.

The product of its (nonzero) digits is 96000, while the sum is 35.

The square root of 645442055 is about 25405.5516570690. The cubic root of 645442055 is about 864.2096001936.

The spelling of 645442055 in words is "six hundred forty-five million, four hundred forty-two thousand, fifty-five".