20765797 has 4 divisors (see below), whose sum is σ = 22363180. Its totient is φ = 19168416.

The previous prime is 20765783. The next prime is 20765807. The reversal of 20765797 is 79756702.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79756702 = 2 ⋅39878351.

It can be written as a sum of positive squares in 2 ways, for example, as 972196 + 19793601 = 986^2 + 4449^2 .

It is a cyclic number.

It is not a de Polignac number, because 20765797 - 2⁷ = 20765669 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20765707) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 798672 + ... + 798697.

It is an arithmetic number, because the mean of its divisors is an integer number (5590795).

Almost surely, 2^20765797 is an apocalyptic number.

It is an amenable number.

20765797 is a deficient number, since it is larger than the sum of its proper divisors (1597383).

20765797 is a wasteful number, since it uses less digits than its factorization.

20765797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1597382.

The product of its (nonzero) digits is 185220, while the sum is 43.

The square root of 20765797 is about 4556.9504056990. The cubic root of 20765797 is about 274.8629487893.

The spelling of 20765797 in words is "twenty million, seven hundred sixty-five thousand, seven hundred ninety-seven".