21013177 has 2 divisors, whose sum is σ = 21013178. Its totient is φ = 21013176.

The previous prime is 21013159. The next prime is 21013189. The reversal of 21013177 is 77131012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21013056 + 121 = 4584^2 + 11^2 .

It is a cyclic number.

It is not a de Polignac number, because 21013177 - 2⁷ = 21013049 is a prime.

It is not a weakly prime, because it can be changed into another prime (21013117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506588 + 10506589.

It is an arithmetic number, because the mean of its divisors is an integer number (10506589).

Almost surely, 2^21013177 is an apocalyptic number.

It is an amenable number.

21013177 is a deficient number, since it is larger than the sum of its proper divisors (1).

21013177 is an equidigital number, since it uses as much as digits as its factorization.

21013177 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 294, while the sum is 22.

The square root of 21013177 is about 4584.0131980613. The cubic root of 21013177 is about 275.9501108805.

Adding to 21013177 its reverse (77131012), we get a palindrome (98144189).

The spelling of 21013177 in words is "twenty-one million, thirteen thousand, one hundred seventy-seven".