21484357 has 2 divisors, whose sum is σ = 21484358. Its totient is φ = 21484356.

The previous prime is 21484349. The next prime is 21484363. The reversal of 21484357 is 75348412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15729156 + 5755201 = 3966^2 + 2399^2 .

It is a cyclic number.

It is not a de Polignac number, because 21484357 - 2³ = 21484349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21484327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10742178 + 10742179.

It is an arithmetic number, because the mean of its divisors is an integer number (10742179).

Almost surely, 2^21484357 is an apocalyptic number.

It is an amenable number.

21484357 is a deficient number, since it is larger than the sum of its proper divisors (1).

21484357 is an equidigital number, since it uses as much as digits as its factorization.

21484357 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26880, while the sum is 34.

The square root of 21484357 is about 4635.1221127388. The cubic root of 21484357 is about 277.9974336840.

The spelling of 21484357 in words is "twenty-one million, four hundred eighty-four thousand, three hundred fifty-seven".