20942913 has 4 divisors (see below), whose sum is σ = 27923888. Its totient is φ = 13961940.

The previous prime is 20942899. The next prime is 20942917. The reversal of 20942913 is 31924902.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-20942913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20942917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3490483 + ... + 3490488.

It is an arithmetic number, because the mean of its divisors is an integer number (6980972).

Almost surely, 2^20942913 is an apocalyptic number.

It is an amenable number.

20942913 is a deficient number, since it is larger than the sum of its proper divisors (6980975).

20942913 is an equidigital number, since it uses as much as digits as its factorization.

20942913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6980974.

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 20942913 is about 4576.3427537718. The cubic root of 20942913 is about 275.6421928179.

The spelling of 20942913 in words is "twenty million, nine hundred forty-two thousand, nine hundred thirteen".