19726961 has 2 divisors, whose sum is σ = 19726962. Its totient is φ = 19726960.

The previous prime is 19726937. The next prime is 19726979. The reversal of 19726961 is 16962791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14776336 + 4950625 = 3844^2 + 2225^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19726961 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19726901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9863480 + 9863481.

It is an arithmetic number, because the mean of its divisors is an integer number (9863481).

Almost surely, 2^19726961 is an apocalyptic number.

It is an amenable number.

19726961 is a deficient number, since it is larger than the sum of its proper divisors (1).

19726961 is an equidigital number, since it uses as much as digits as its factorization.

19726961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40824, while the sum is 41.

The square root of 19726961 is about 4441.5043622629. The cubic root of 19726961 is about 270.2008610531.

The spelling of 19726961 in words is "nineteen million, seven hundred twenty-six thousand, nine hundred sixty-one".