645154261 has 8 divisors (see below), whose sum is σ = 650677248. Its totient is φ = 639654000.

The previous prime is 645154259. The next prime is 645154273. The reversal of 645154261 is 162451546.

645154261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 645154261 - 2¹ = 645154259 is a prime.

It is a super-2 number, since 2×645154261² = 832448040972912242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645104261) 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, 53971 + ... + 64831.

It is an arithmetic number, because the mean of its divisors is an integer number (81334656).

Almost surely, 2^645154261 is an apocalyptic number.

It is an amenable number.

645154261 is a deficient number, since it is larger than the sum of its proper divisors (5522987).

645154261 is a wasteful number, since it uses less digits than its factorization.

645154261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11363.

The product of its digits is 28800, while the sum is 34.

The square root of 645154261 is about 25399.8870273078. The cubic root of 645154261 is about 864.0811345883.

The spelling of 645154261 in words is "six hundred forty-five million, one hundred fifty-four thousand, two hundred sixty-one".