10021001100021 has 12 divisors (see below), whose sum is σ = 14474864403948. Its totient is φ = 6680628152064.

The previous prime is 10021001099971. The next prime is 10021001100113. The reversal of 10021001100021 is 12000110012001.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 7763389673796 + 2257611426225 = 2786286^2 + 1502535^2 .

It is not a de Polignac number, because 10021001100021 - 2⁶ = 10021001099957 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 10021001099976 and 10021001100012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10021011100021) 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, 1609180 + ... + 4757253.

It is an arithmetic number, because the mean of its divisors is an integer number (1206238700329).

Almost surely, 2^{10021001100021} is an apocalyptic number.

It is an amenable number.

10021001100021 is a deficient number, since it is larger than the sum of its proper divisors (4453863303927).

10021001100021 is a wasteful number, since it uses less digits than its factorization.

10021001100021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6541332 (or 6541329 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 10021001100021 its reverse (12000110012001), we get a palindrome (22021111112022).

The spelling of 10021001100021 in words is "ten trillion, twenty-one billion, one million, one hundred thousand, twenty-one".