20870489 has 2 divisors, whose sum is σ = 20870490. Its totient is φ = 20870488.

The previous prime is 20870467. The next prime is 20870497. The reversal of 20870489 is 98407802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18421264 + 2449225 = 4292^2 + 1565^2 .

It is a cyclic number.

It is not a de Polignac number, because 20870489 - 2²⁰ = 19821913 is a prime.

It is a super-2 number, since 2×20870489² = 871154622198242, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20870429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10435244 + 10435245.

It is an arithmetic number, because the mean of its divisors is an integer number (10435245).

Almost surely, 2^20870489 is an apocalyptic number.

It is an amenable number.

20870489 is a deficient number, since it is larger than the sum of its proper divisors (1).

20870489 is an equidigital number, since it uses as much as digits as its factorization.

20870489 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 20870489 is about 4568.4230320757. The cubic root of 20870489 is about 275.3240873347.

The spelling of 20870489 in words is "twenty million, eight hundred seventy thousand, four hundred eighty-nine".