21101002021 has 8 divisors (see below), whose sum is σ = 24373350144. Its totient is φ = 18054333120.

The previous prime is 21101002019. The next prime is 21101002031. The reversal of 21101002021 is 12020010112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21101002021 - 2¹ = 21101002019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21101001989 and 21101002007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101002031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56419605 + ... + 56419978.

It is an arithmetic number, because the mean of its divisors is an integer number (3046668768).

Almost surely, 2^21101002021 is an apocalyptic number.

It is an amenable number.

21101002021 is a deficient number, since it is larger than the sum of its proper divisors (3272348123).

21101002021 is a wasteful number, since it uses less digits than its factorization.

21101002021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112839611.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21101002021 its reverse (12020010112), we get a palindrome (33121012133).

The spelling of 21101002021 in words is "twenty-one billion, one hundred one million, two thousand, twenty-one".