20616451 has 2 divisors, whose sum is σ = 20616452. Its totient is φ = 20616450.

The previous prime is 20616433. The next prime is 20616473. The reversal of 20616451 is 15461602.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20616451 is a prime.

It is not a weakly prime, because it can be changed into another prime (20610451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10308225 + 10308226.

It is an arithmetic number, because the mean of its divisors is an integer number (10308226).

Almost surely, 2^20616451 is an apocalyptic number.

20616451 is a deficient number, since it is larger than the sum of its proper divisors (1).

20616451 is an equidigital number, since it uses as much as digits as its factorization.

20616451 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 20616451 is about 4540.5342196706. The cubic root of 20616451 is about 274.2024317903.

The spelling of 20616451 in words is "twenty million, six hundred sixteen thousand, four hundred fifty-one".