646132291 has 4 divisors (see below), whose sum is σ = 738436912. Its totient is φ = 553827672.

The previous prime is 646132283. The next prime is 646132301. The reversal of 646132291 is 192231646.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 646132291 - 2³ = 646132283 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646132241) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46152300 + ... + 46152313.

It is an arithmetic number, because the mean of its divisors is an integer number (184609228).

Almost surely, 2^646132291 is an apocalyptic number.

646132291 is a deficient number, since it is larger than the sum of its proper divisors (92304621).

646132291 is an equidigital number, since it uses as much as digits as its factorization.

646132291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92304620.

The product of its digits is 15552, while the sum is 34.

The square root of 646132291 is about 25419.1323809449. The cubic root of 646132291 is about 864.5175524793.

The spelling of 646132291 in words is "six hundred forty-six million, one hundred thirty-two thousand, two hundred ninety-one".