1646268261 has 16 divisors (see below), whose sum is σ = 2417825280. Its totient is φ = 988049520.

The previous prime is 1646268199. The next prime is 1646268271. The reversal of 1646268261 is 1628626461.

It is not a de Polignac number, because 1646268261 - 2¹⁷ = 1646137189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1646268271) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 238771 + ... + 245568.

It is an arithmetic number, because the mean of its divisors is an integer number (151114080).

Almost surely, 2^1646268261 is an apocalyptic number.

1646268261 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1646268261 is a deficient number, since it is larger than the sum of its proper divisors (771557019).

1646268261 is a wasteful number, since it uses less digits than its factorization.

1646268261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 484456.

The product of its digits is 165888, while the sum is 42.

The square root of 1646268261 is about 40574.2314899494. The cubic root of 1646268261 is about 1180.7742359747.

The spelling of 1646268261 in words is "one billion, six hundred forty-six million, two hundred sixty-eight thousand, two hundred sixty-one".