20649313 has 2 divisors, whose sum is σ = 20649314. Its totient is φ = 20649312.

The previous prime is 20649289. The next prime is 20649319. The reversal of 20649313 is 31394602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19421649 + 1227664 = 4407^2 + 1108^2 .

It is a cyclic number.

It is not a de Polignac number, because 20649313 - 2¹⁷ = 20518241 is a prime.

It is not a weakly prime, because it can be changed into another prime (20649319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10324656 + 10324657.

It is an arithmetic number, because the mean of its divisors is an integer number (10324657).

Almost surely, 2^20649313 is an apocalyptic number.

It is an amenable number.

20649313 is a deficient number, since it is larger than the sum of its proper divisors (1).

20649313 is an equidigital number, since it uses as much as digits as its factorization.

20649313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 28.

The square root of 20649313 is about 4544.1515159598. The cubic root of 20649313 is about 274.3480445808.

The spelling of 20649313 in words is "twenty million, six hundred forty-nine thousand, three hundred thirteen".