645421460 has 12 divisors (see below), whose sum is σ = 1355385108. Its totient is φ = 258168576.

The previous prime is 645421429. The next prime is 645421471. The reversal of 645421460 is 64124546.

It can be written as a sum of positive squares in 2 ways, for example, as 96550276 + 548871184 = 9826^2 + 23428^2 .

It is a super-2 number, since 2×645421460² = 833137722057063200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

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, 16135517 + ... + 16135556.

It is an arithmetic number, because the mean of its divisors is an integer number (112948759).

Almost surely, 2^645421460 is an apocalyptic number.

It is an amenable number.

645421460 is an abundant number, since it is smaller than the sum of its proper divisors (709963648).

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

645421460 is a wasteful number, since it uses less digits than its factorization.

645421460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32271082 (or 32271080 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 32.

The square root of 645421460 is about 25405.1463290413. The cubic root of 645421460 is about 864.2004082577.

The spelling of 645421460 in words is "six hundred forty-five million, four hundred twenty-one thousand, four hundred sixty".