21001012112021 has 8 divisors (see below), whose sum is σ = 21725360162400. Its totient is φ = 20276675742960.

The previous prime is 21001012111943. The next prime is 21001012112023. The reversal of 21001012112021 is 12021121010012.

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 21001012112021 - 2¹⁰ = 21001012110997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21001012111987 and 21001012112005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001012112023) 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, 818486 + ... + 6532376.

It is an arithmetic number, because the mean of its divisors is an integer number (2715670020300).

Almost surely, 2^{21001012112021} is an apocalyptic number.

It is an amenable number.

21001012112021 is a deficient number, since it is larger than the sum of its proper divisors (724348050379).

21001012112021 is a wasteful number, since it uses less digits than its factorization.

21001012112021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5840659.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21001012112021 its reverse (12021121010012), we get a palindrome (33022133122033).

The spelling of 21001012112021 in words is "twenty-one trillion, one billion, twelve million, one hundred twelve thousand, twenty-one".