21059377 has 2 divisors, whose sum is σ = 21059378. Its totient is φ = 21059376.

The previous prime is 21059371. The next prime is 21059383. The reversal of 21059377 is 77395012.

It is a balanced prime because it is at equal distance from previous prime (21059371) and next prime (21059383).

It can be written as a sum of positive squares in only one way, i.e., 19088161 + 1971216 = 4369^2 + 1404^2 .

It is a cyclic number.

It is not a de Polignac number, because 21059377 - 2³ = 21059369 is a prime.

It is not a weakly prime, because it can be changed into another prime (21059371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10529688 + 10529689.

It is an arithmetic number, because the mean of its divisors is an integer number (10529689).

Almost surely, 2^21059377 is an apocalyptic number.

It is an amenable number.

21059377 is a deficient number, since it is larger than the sum of its proper divisors (1).

21059377 is an equidigital number, since it uses as much as digits as its factorization.

21059377 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13230, while the sum is 34.

The square root of 21059377 is about 4589.0496837581. The cubic root of 21059377 is about 276.1521993635.

The spelling of 21059377 in words is "twenty-one million, fifty-nine thousand, three hundred seventy-seven".