645626271 has 8 divisors (see below), whose sum is σ = 873683584. Its totient is φ = 423993240.

The previous prime is 645626269. The next prime is 645626281. The reversal of 645626271 is 172626546.

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

It is not a de Polignac number, because 645626271 - 2¹ = 645626269 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 (645626281) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1605835 + ... + 1606236.

It is an arithmetic number, because the mean of its divisors is an integer number (109210448).

Almost surely, 2^645626271 is an apocalyptic number.

645626271 is a deficient number, since it is larger than the sum of its proper divisors (228057313).

645626271 is a wasteful number, since it uses less digits than its factorization.

645626271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3212141.

The product of its digits is 120960, while the sum is 39.

The square root of 645626271 is about 25409.1769052049. The cubic root of 645626271 is about 864.2918105645.

It can be divided in two parts, 64 and 5626271, that added together give a triangular number (5626335 = T₃₃₅₄).

The spelling of 645626271 in words is "six hundred forty-five million, six hundred twenty-six thousand, two hundred seventy-one".