20551129 has 2 divisors, whose sum is σ = 20551130. Its totient is φ = 20551128.

The previous prime is 20551073. The next prime is 20551159. The reversal of 20551129 is 92115502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15366400 + 5184729 = 3920^2 + 2277^2 .

It is a cyclic number.

It is not a de Polignac number, because 20551129 - 2⁷ = 20551001 is a prime.

It is equal to p_1303288 and since 20551129 and 1303288 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 (20551159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10275564 + 10275565.

It is an arithmetic number, because the mean of its divisors is an integer number (10275565).

Almost surely, 2^20551129 is an apocalyptic number.

It is an amenable number.

20551129 is a deficient number, since it is larger than the sum of its proper divisors (1).

20551129 is an equidigital number, since it uses as much as digits as its factorization.

20551129 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 20551129 is about 4533.3353063721. The cubic root of 20551129 is about 273.9125273552.

The spelling of 20551129 in words is "twenty million, five hundred fifty-one thousand, one hundred twenty-nine".