20713529 has 2 divisors, whose sum is σ = 20713530. Its totient is φ = 20713528.

The previous prime is 20713489. The next prime is 20713541. The reversal of 20713529 is 92531702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15642025 + 5071504 = 3955^2 + 2252^2 .

It is a cyclic number.

It is not a de Polignac number, because 20713529 - 2¹² = 20709433 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20713129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10356764 + 10356765.

It is an arithmetic number, because the mean of its divisors is an integer number (10356765).

Almost surely, 2^20713529 is an apocalyptic number.

It is an amenable number.

20713529 is a deficient number, since it is larger than the sum of its proper divisors (1).

20713529 is an equidigital number, since it uses as much as digits as its factorization.

20713529 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 20713529 is about 4551.2118166484. The cubic root of 20713529 is about 274.6321428615.

The spelling of 20713529 in words is "twenty million, seven hundred thirteen thousand, five hundred twenty-nine".