21292541 has 2 divisors, whose sum is σ = 21292542. Its totient is φ = 21292540.

The previous prime is 21292519. The next prime is 21292543. The reversal of 21292541 is 14529212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16687225 + 4605316 = 4085^2 + 2146^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21292541 is a prime.

It is a Sophie Germain prime.

Together with 21292543, it forms a pair of twin primes.

It is a Chen prime.

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21292541.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21292543) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10646270 + 10646271.

It is an arithmetic number, because the mean of its divisors is an integer number (10646271).

Almost surely, 2^21292541 is an apocalyptic number.

It is an amenable number.

21292541 is a deficient number, since it is larger than the sum of its proper divisors (1).

21292541 is an equidigital number, since it uses as much as digits as its factorization.

21292541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 26.

The square root of 21292541 is about 4614.3841409228. The cubic root of 21292541 is about 277.1676230468.

The spelling of 21292541 in words is "twenty-one million, two hundred ninety-two thousand, five hundred forty-one".