21692329 has 2 divisors, whose sum is σ = 21692330. Its totient is φ = 21692328.

The previous prime is 21692309. The next prime is 21692371. The reversal of 21692329 is 92329612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16216729 + 5475600 = 4027^2 + 2340^2 .

It is a cyclic number.

It is not a de Polignac number, because 21692329 - 2¹¹ = 21690281 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 21692294 and 21692303.

It is not a weakly prime, because it can be changed into another prime (21692309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10846164 + 10846165.

It is an arithmetic number, because the mean of its divisors is an integer number (10846165).

Almost surely, 2^21692329 is an apocalyptic number.

It is an amenable number.

21692329 is a deficient number, since it is larger than the sum of its proper divisors (1).

21692329 is an equidigital number, since it uses as much as digits as its factorization.

21692329 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11664, while the sum is 34.

The square root of 21692329 is about 4657.5024422967. The cubic root of 21692329 is about 278.8915745406.

The spelling of 21692329 in words is "twenty-one million, six hundred ninety-two thousand, three hundred twenty-nine".