21532697 has 2 divisors, whose sum is σ = 21532698. Its totient is φ = 21532696.

The previous prime is 21532663. The next prime is 21532717. The reversal of 21532697 is 79623512.

21532697 is nontrivially palindromic in base 13.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21381376 + 151321 = 4624^2 + 389^2 .

It is a cyclic number.

It is not a de Polignac number, because 21532697 - 2⁶ = 21532633 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21532097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10766348 + 10766349.

It is an arithmetic number, because the mean of its divisors is an integer number (10766349).

Almost surely, 2^21532697 is an apocalyptic number.

It is an amenable number.

21532697 is a deficient number, since it is larger than the sum of its proper divisors (1).

21532697 is an equidigital number, since it uses as much as digits as its factorization.

21532697 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22680, while the sum is 35.

The square root of 21532697 is about 4640.3337164476. Note that the first 3 decimals coincide. The cubic root of 21532697 is about 278.2057764282.

The spelling of 21532697 in words is "twenty-one million, five hundred thirty-two thousand, six hundred ninety-seven".