645405534 has 24 divisors (see below), whose sum is σ = 1405014312. Its totient is φ = 214114320.

The previous prime is 645405529. The next prime is 645405557. The reversal of 645405534 is 435504546.

645405534 is a `hidden beast` number, since 64 + 5 + 40 + 553 + 4 = 666.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 81169 + ... + 88764.

It is an arithmetic number, because the mean of its divisors is an integer number (58542263).

Almost surely, 2^645405534 is an apocalyptic number.

645405534 is an abundant number, since it is smaller than the sum of its proper divisors (759608778).

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

645405534 is a wasteful number, since it uses less digits than its factorization.

645405534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170152 (or 170149 counting only the distinct ones).

The product of its (nonzero) digits is 144000, while the sum is 36.

The square root of 645405534 is about 25404.8328866773. The cubic root of 645405534 is about 864.1933000502.

The spelling of 645405534 in words is "six hundred forty-five million, four hundred five thousand, five hundred thirty-four".