20707989 has 16 divisors (see below), whose sum is σ = 29439360. Its totient is φ = 12902400.

The previous prime is 20707987. The next prime is 20707991. The reversal of 20707989 is 98970702.

It is an interprime number because it is at equal distance from previous prime (20707987) and next prime (20707991).

It is not a de Polignac number, because 20707989 - 2¹ = 20707987 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20707989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20707987) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6357 + ... + 9045.

It is an arithmetic number, because the mean of its divisors is an integer number (1839960).

Almost surely, 2^20707989 is an apocalyptic number.

It is an amenable number.

20707989 is a deficient number, since it is larger than the sum of its proper divisors (8731371).

20707989 is a wasteful number, since it uses less digits than its factorization.

20707989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2860.

The product of its (nonzero) digits is 63504, while the sum is 42.

The square root of 20707989 is about 4550.6031468367. The cubic root of 20707989 is about 274.6076564862.

The spelling of 20707989 in words is "twenty million, seven hundred seven thousand, nine hundred eighty-nine".