21536797 has 2 divisors, whose sum is σ = 21536798. Its totient is φ = 21536796.

The previous prime is 21536791. The next prime is 21536803. The reversal of 21536797 is 79763512.

It is a balanced prime because it is at equal distance from previous prime (21536791) and next prime (21536803).

It can be written as a sum of positive squares in only one way, i.e., 10850436 + 10686361 = 3294^2 + 3269^2 .

It is a cyclic number.

It is not a de Polignac number, because 21536797 - 2²³ = 13148189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21536791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10768398 + 10768399.

It is an arithmetic number, because the mean of its divisors is an integer number (10768399).

Almost surely, 2^21536797 is an apocalyptic number.

It is an amenable number.

21536797 is a deficient number, since it is larger than the sum of its proper divisors (1).

21536797 is an equidigital number, since it uses as much as digits as its factorization.

21536797 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 79380, while the sum is 40.

The square root of 21536797 is about 4640.7754739914. The cubic root of 21536797 is about 278.2234328524.

The spelling of 21536797 in words is "twenty-one million, five hundred thirty-six thousand, seven hundred ninety-seven".