20010010021 has 12 divisors (see below), whose sum is σ = 21261517092. Its totient is φ = 18828336128.

The previous prime is 20010010003. The next prime is 20010010049. The reversal of 20010010021 is 12001001002.

It can be written as a sum of positive squares in 6 ways, for example, as 1182328225 + 18827681796 = 34385^2 + 137214^2 .

It is not a de Polignac number, because 20010010021 - 2⁷ = 20010009893 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20010009986 and 20010010013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20010010921) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1969671 + ... + 1979803.

It is an arithmetic number, because the mean of its divisors is an integer number (1771793091).

Almost surely, 2^20010010021 is an apocalyptic number.

It is an amenable number.

20010010021 is a deficient number, since it is larger than the sum of its proper divisors (1251507071).

20010010021 is a wasteful number, since it uses less digits than its factorization.

20010010021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17000 (or 16983 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 20010010021 its reverse (12001001002), we get a palindrome (32011011023).

The spelling of 20010010021 in words is "twenty billion, ten million, ten thousand, twenty-one".