20746421 has 2 divisors, whose sum is σ = 20746422. Its totient is φ = 20746420.

The previous prime is 20746417. The next prime is 20746441. The reversal of 20746421 is 12464702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11662225 + 9084196 = 3415^2 + 3014^2 .

It is a cyclic number.

It is not a de Polignac number, because 20746421 - 2² = 20746417 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 (20746441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10373210 + 10373211.

It is an arithmetic number, because the mean of its divisors is an integer number (10373211).

Almost surely, 2^20746421 is an apocalyptic number.

It is an amenable number.

20746421 is a deficient number, since it is larger than the sum of its proper divisors (1).

20746421 is an equidigital number, since it uses as much as digits as its factorization.

20746421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 20746421 is about 4554.8239263445. The cubic root of 20746421 is about 274.7774331408. Note that the first 3 decimals are identical.

The spelling of 20746421 in words is "twenty million, seven hundred forty-six thousand, four hundred twenty-one".