20630551 has 2 divisors, whose sum is σ = 20630552. Its totient is φ = 20630550.

The previous prime is 20630543. The next prime is 20630557. The reversal of 20630551 is 15503602.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20630551 - 2³ = 20630543 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20630557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10315275 + 10315276.

It is an arithmetic number, because the mean of its divisors is an integer number (10315276).

Almost surely, 2^20630551 is an apocalyptic number.

20630551 is a deficient number, since it is larger than the sum of its proper divisors (1).

20630551 is an equidigital number, since it uses as much as digits as its factorization.

20630551 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 20630551 is about 4542.0866350170. The cubic root of 20630551 is about 274.2649283733.

The spelling of 20630551 in words is "twenty million, six hundred thirty thousand, five hundred fifty-one".