20804951 has 2 divisors, whose sum is σ = 20804952. Its totient is φ = 20804950.

The previous prime is 20804947. The next prime is 20804963. The reversal of 20804951 is 15940802.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20804951 - 2² = 20804947 is a prime.

It is a super-2 number, since 2×20804951² = 865691972224802, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20804911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10402475 + 10402476.

It is an arithmetic number, because the mean of its divisors is an integer number (10402476).

Almost surely, 2^20804951 is an apocalyptic number.

20804951 is a deficient number, since it is larger than the sum of its proper divisors (1).

20804951 is an equidigital number, since it uses as much as digits as its factorization.

20804951 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 20804951 is about 4561.2444573822. The cubic root of 20804951 is about 275.0355920875.

The spelling of 20804951 in words is "twenty million, eight hundred four thousand, nine hundred fifty-one".