20778203 has 2 divisors, whose sum is σ = 20778204. Its totient is φ = 20778202.

The previous prime is 20778179. The next prime is 20778211. The reversal of 20778203 is 30287702.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20778203 - 2⁶ = 20778139 is a prime.

It is a Sophie Germain prime.

It is equal to p_1316846 and since 20778203 and 1316846 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (20778253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10389101 + 10389102.

It is an arithmetic number, because the mean of its divisors is an integer number (10389102).

Almost surely, 2^20778203 is an apocalyptic number.

20778203 is a deficient number, since it is larger than the sum of its proper divisors (1).

20778203 is an equidigital number, since it uses as much as digits as its factorization.

20778203 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4704, while the sum is 29.

The square root of 20778203 is about 4558.3114198133. The cubic root of 20778203 is about 274.9176745306.

The spelling of 20778203 in words is "twenty million, seven hundred seventy-eight thousand, two hundred three".