20100001021 has 8 divisors (see below), whose sum is σ = 20459769120. Its totient is φ = 19743033072.

The previous prime is 20100001013. The next prime is 20100001037. The reversal of 20100001021 is 12010000102.

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 20100001021 - 2³ = 20100001013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20100000995 and 20100001013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20100001121) 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, 685551 + ... + 714268.

It is an arithmetic number, because the mean of its divisors is an integer number (2557471140).

Almost surely, 2^20100001021 is an apocalyptic number.

It is an amenable number.

20100001021 is a deficient number, since it is larger than the sum of its proper divisors (359768099).

20100001021 is a wasteful number, since it uses less digits than its factorization.

20100001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1400075.

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 20100001021 its reverse (12010000102), we get a palindrome (32110001123).

The spelling of 20100001021 in words is "twenty billion, one hundred million, one thousand, twenty-one".