20898869 has 2 divisors, whose sum is σ = 20898870. Its totient is φ = 20898868.

The previous prime is 20898863. The next prime is 20898883. The reversal of 20898869 is 96889802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20811844 + 87025 = 4562^2 + 295^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20898869 is a prime.

It is a super-2 number, since 2×20898869² = 873525450958322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20898863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10449434 + 10449435.

It is an arithmetic number, because the mean of its divisors is an integer number (10449435).

Almost surely, 2^20898869 is an apocalyptic number.

It is an amenable number.

20898869 is a deficient number, since it is larger than the sum of its proper divisors (1).

20898869 is an equidigital number, since it uses as much as digits as its factorization.

20898869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 497664, while the sum is 50.

The square root of 20898869 is about 4571.5280815062. The cubic root of 20898869 is about 275.4488274010.

The spelling of 20898869 in words is "twenty million, eight hundred ninety-eight thousand, eight hundred sixty-nine".