20649291 has 16 divisors (see below), whose sum is σ = 30060576. Its totient is φ = 12531456.

The previous prime is 20649289. The next prime is 20649313. The reversal of 20649291 is 19294602.

It is not a de Polignac number, because 20649291 - 2¹ = 20649289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20649191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 780 + ... + 6473.

It is an arithmetic number, because the mean of its divisors is an integer number (1878786).

Almost surely, 2^20649291 is an apocalyptic number.

20649291 is a deficient number, since it is larger than the sum of its proper divisors (9411285).

20649291 is a wasteful number, since it uses less digits than its factorization.

20649291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7342.

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 20649291 is about 4544.1490952653. The cubic root of 20649291 is about 274.3479471496.

The spelling of 20649291 in words is "twenty million, six hundred forty-nine thousand, two hundred ninety-one".