20820407 has 2 divisors, whose sum is σ = 20820408. Its totient is φ = 20820406.

The previous prime is 20820383. The next prime is 20820413. The reversal of 20820407 is 70402802.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20820407 - 2²⁴ = 4043191 is a prime.

It is a Chen prime.

It is equal to p_1319306 and since 20820407 and 1319306 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20820607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10410203 + 10410204.

It is an arithmetic number, because the mean of its divisors is an integer number (10410204).

Almost surely, 2^20820407 is an apocalyptic number.

20820407 is a deficient number, since it is larger than the sum of its proper divisors (1).

20820407 is an equidigital number, since it uses as much as digits as its factorization.

20820407 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 896, while the sum is 23.

The square root of 20820407 is about 4562.9384172921. The cubic root of 20820407 is about 275.1036832175.

The spelling of 20820407 in words is "twenty million, eight hundred twenty thousand, four hundred seven".