21134657 has 2 divisors, whose sum is σ = 21134658. Its totient is φ = 21134656.

The previous prime is 21134611. The next prime is 21134713. The reversal of 21134657 is 75643112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19149376 + 1985281 = 4376^2 + 1409^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21134657 is a prime.

It is equal to p_1337942 and since 21134657 and 1337942 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (21134857) 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, 10567328 + 10567329.

It is an arithmetic number, because the mean of its divisors is an integer number (10567329).

Almost surely, 2^21134657 is an apocalyptic number.

It is an amenable number.

21134657 is a deficient number, since it is larger than the sum of its proper divisors (1).

21134657 is an equidigital number, since it uses as much as digits as its factorization.

21134657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5040, while the sum is 29.

The square root of 21134657 is about 4597.2445007852. The cubic root of 21134657 is about 276.4808576423.

Adding to 21134657 its reverse (75643112), we get a palindrome (96777769).

The spelling of 21134657 in words is "twenty-one million, one hundred thirty-four thousand, six hundred fifty-seven".