20763121 has 4 divisors (see below), whose sum is σ = 21154932. Its totient is φ = 20371312.

The previous prime is 20763091. The next prime is 20763131. The reversal of 20763121 is 12136702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12136702 = 2 ⋅6068351.

It can be written as a sum of positive squares in 2 ways, for example, as 5239521 + 15523600 = 2289^2 + 3940^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20763121 is a prime.

It is a super-2 number, since 2×20763121² = 862214387321282, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20763092 and 20763101.

It is not an unprimeable number, because it can be changed into a prime (20763131) 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, 195826 + ... + 195931.

It is an arithmetic number, because the mean of its divisors is an integer number (5288733).

Almost surely, 2^20763121 is an apocalyptic number.

It is an amenable number.

20763121 is a deficient number, since it is larger than the sum of its proper divisors (391811).

20763121 is an equidigital number, since it uses as much as digits as its factorization.

20763121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391810.

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 20763121 is about 4556.6567788237. The cubic root of 20763121 is about 274.8511414754.

Adding to 20763121 its reverse (12136702), we get a palindrome (32899823).

The spelling of 20763121 in words is "twenty million, seven hundred sixty-three thousand, one hundred twenty-one".