20780713 has 4 divisors (see below), whose sum is σ = 21043840. Its totient is φ = 20517588.

The previous prime is 20780689. The next prime is 20780729. The reversal of 20780713 is 31708702.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 31708702 = 2 ⋅15854351.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20780713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20780743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131445 + ... + 131602.

It is an arithmetic number, because the mean of its divisors is an integer number (5260960).

Almost surely, 2^20780713 is an apocalyptic number.

It is an amenable number.

20780713 is a deficient number, since it is larger than the sum of its proper divisors (263127).

20780713 is an equidigital number, since it uses as much as digits as its factorization.

20780713 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263126.

The product of its (nonzero) digits is 2352, while the sum is 28.

The square root of 20780713 is about 4558.5867327495. The cubic root of 20780713 is about 274.9287440727.

The spelling of 20780713 in words is "twenty million, seven hundred eighty thousand, seven hundred thirteen".