21094357 has 2 divisors, whose sum is σ = 21094358. Its totient is φ = 21094356.

The previous prime is 21094279. The next prime is 21094373. The reversal of 21094357 is 75349012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20304036 + 790321 = 4506^2 + 889^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21094357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21094387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10547178 + 10547179.

It is an arithmetic number, because the mean of its divisors is an integer number (10547179).

Almost surely, 2^21094357 is an apocalyptic number.

It is an amenable number.

21094357 is a deficient number, since it is larger than the sum of its proper divisors (1).

21094357 is an equidigital number, since it uses as much as digits as its factorization.

21094357 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 21094357 is about 4592.8593490330. The cubic root of 21094357 is about 276.3050126922.

The spelling of 21094357 in words is "twenty-one million, ninety-four thousand, three hundred fifty-seven".