645634 has 8 divisors (see below), whose sum is σ = 1056528. Its totient is φ = 293460.

The previous prime is 645629. The next prime is 645641. The reversal of 645634 is 436546.

645634 is nontrivially palindromic in base 3.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14652 + ... + 14695.

It is an arithmetic number, because the mean of its divisors is an integer number (132066).

2⁶⁴⁵⁶³⁴ is an apocalyptic number.

645634 is a deficient number, since it is larger than the sum of its proper divisors (410894).

645634 is a wasteful number, since it uses less digits than its factorization.

645634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29360.

The product of its digits is 8640, while the sum is 28.

The square root of 645634 is about 803.5135344224. The cubic root of 645634 is about 86.4295259456.

The spelling of 645634 in words is "six hundred forty-five thousand, six hundred thirty-four".