20869613 has 2 divisors, whose sum is σ = 20869614. Its totient is φ = 20869612.

The previous prime is 20869609. The next prime is 20869627. The reversal of 20869613 is 31696802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20775364 + 94249 = 4558^2 + 307^2 .

It is a cyclic number.

It is not a de Polignac number, because 20869613 - 2² = 20869609 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20869633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10434806 + 10434807.

It is an arithmetic number, because the mean of its divisors is an integer number (10434807).

Almost surely, 2^20869613 is an apocalyptic number.

It is an amenable number.

20869613 is a deficient number, since it is larger than the sum of its proper divisors (1).

20869613 is an equidigital number, since it uses as much as digits as its factorization.

20869613 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 20869613 is about 4568.3271555352. The cubic root of 20869613 is about 275.3202352085.

The spelling of 20869613 in words is "twenty million, eight hundred sixty-nine thousand, six hundred thirteen".