20980913 has 2 divisors, whose sum is σ = 20980914. Its totient is φ = 20980912.

The previous prime is 20980903. The next prime is 20980919. The reversal of 20980913 is 31908902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12588304 + 8392609 = 3548^2 + 2897^2 .

It is a cyclic number.

It is not a de Polignac number, because 20980913 - 2²⁰ = 19932337 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20980913.

It is not a weakly prime, because it can be changed into another prime (20980919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10490456 + 10490457.

It is an arithmetic number, because the mean of its divisors is an integer number (10490457).

Almost surely, 2^20980913 is an apocalyptic number.

It is an amenable number.

20980913 is a deficient number, since it is larger than the sum of its proper divisors (1).

20980913 is an equidigital number, since it uses as much as digits as its factorization.

20980913 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 20980913 is about 4580.4926590925. The cubic root of 20980913 is about 275.8088056572.

The spelling of 20980913 in words is "twenty million, nine hundred eighty thousand, nine hundred thirteen".