21170629 has 2 divisors, whose sum is σ = 21170630. Its totient is φ = 21170628.

The previous prime is 21170587. The next prime is 21170641. The reversal of 21170629 is 92607112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16769025 + 4401604 = 4095^2 + 2098^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21170629 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21170597 and 21170606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21170329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10585314 + 10585315.

It is an arithmetic number, because the mean of its divisors is an integer number (10585315).

Almost surely, 2^21170629 is an apocalyptic number.

It is an amenable number.

21170629 is a deficient number, since it is larger than the sum of its proper divisors (1).

21170629 is an equidigital number, since it uses as much as digits as its factorization.

21170629 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 21170629 is about 4601.1551810388. The cubic root of 21170629 is about 276.6376290874.

The spelling of 21170629 in words is "twenty-one million, one hundred seventy thousand, six hundred twenty-nine".