20984263 has 4 divisors (see below), whose sum is σ = 21279888. Its totient is φ = 20688640.

The previous prime is 20984261. The next prime is 20984269. The reversal of 20984263 is 36248902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36248902 = 2 ⋅18124451.

It is a cyclic number.

It is not a de Polignac number, because 20984263 - 2¹ = 20984261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20984261) 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, 147706 + ... + 147847.

It is an arithmetic number, because the mean of its divisors is an integer number (5319972).

Almost surely, 2^20984263 is an apocalyptic number.

20984263 is a deficient number, since it is larger than the sum of its proper divisors (295625).

20984263 is an equidigital number, since it uses as much as digits as its factorization.

20984263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 295624.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 20984263 is about 4580.8583256853. The cubic root of 20984263 is about 275.8234842419.

The spelling of 20984263 in words is "twenty million, nine hundred eighty-four thousand, two hundred sixty-three".