20202610921 has 4 divisors (see below), whose sum is σ = 20212978500. Its totient is φ = 20192243344.

The previous prime is 20202610913. The next prime is 20202610931. The reversal of 20202610921 is 12901620202.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10858682025 + 9343928896 = 104205^2 + 96664^2 .

It is a cyclic number.

It is not a de Polignac number, because 20202610921 - 2³ = 20202610913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20202610931) 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, 5180866 + ... + 5184763.

It is an arithmetic number, because the mean of its divisors is an integer number (5053244625).

Almost surely, 2^20202610921 is an apocalyptic number.

It is an amenable number.

20202610921 is a deficient number, since it is larger than the sum of its proper divisors (10367579).

20202610921 is a wasteful number, since it uses less digits than its factorization.

20202610921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10367578.

The product of its (nonzero) digits is 864, while the sum is 25.

The spelling of 20202610921 in words is "twenty billion, two hundred two million, six hundred ten thousand, nine hundred twenty-one".