10100021009 has 4 divisors (see below), whose sum is σ = 10876945716. Its totient is φ = 9323096304.

The previous prime is 10100020991. The next prime is 10100021033. The reversal of 10100021009 is 90012000101.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90012000101 = 233 ⋅386317597.

It can be written as a sum of positive squares in 2 ways, for example, as 3436890625 + 6663130384 = 58625^2 + 81628^2 .

It is a cyclic number.

It is not a de Polignac number, because 10100021009 - 2⁸ = 10100020753 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 10100020984 and 10100021002.

It is not an unprimeable number, because it can be changed into a prime (10100021059) 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, 388462334 + ... + 388462359.

It is an arithmetic number, because the mean of its divisors is an integer number (2719236429).

Almost surely, 2^10100021009 is an apocalyptic number.

It is an amenable number.

10100021009 is a deficient number, since it is larger than the sum of its proper divisors (776924707).

10100021009 is an equidigital number, since it uses as much as digits as its factorization.

10100021009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 776924706.

The product of its (nonzero) digits is 18, while the sum is 14.

The spelling of 10100021009 in words is "ten billion, one hundred million, twenty-one thousand, nine".