21101012001 has 40 divisors (see below), whose sum is σ = 33229310400. Its totient is φ = 13307263200.

The previous prime is 21101011993. The next prime is 21101012029. The reversal of 21101012001 is 10021010112.

It is a happy number.

It is not a de Polignac number, because 21101012001 - 2³ = 21101011993 is a prime.

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

It is not an unprimeable number, because it can be changed into a prime (21101017001) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1069060 + ... + 1088618.

It is an arithmetic number, because the mean of its divisors is an integer number (830732760).

Almost surely, 2^21101012001 is an apocalyptic number.

It is an amenable number.

21101012001 is a deficient number, since it is larger than the sum of its proper divisors (12128298399).

21101012001 is a wasteful number, since it uses less digits than its factorization.

21101012001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20291 (or 20282 counting only the distinct ones).

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

Adding to 21101012001 its reverse (10021010112), we get a palindrome (31122022113).

The spelling of 21101012001 in words is "twenty-one billion, one hundred one million, twelve thousand, one".