101002020021 has 12 divisors (see below), whose sum is σ = 166733493472. Its totient is φ = 57715439976.

The previous prime is 101002020019. The next prime is 101002020047. The reversal of 101002020021 is 120020200101.

It is not a de Polignac number, because 101002020021 - 2¹ = 101002020019 is a prime.

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

It is a junction number, because it is equal to n+sod(n) for n = 101002019985 and 101002020012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101002020001) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 801603271 + ... + 801603396.

Almost surely, 2^101002020021 is an apocalyptic number.

It is an amenable number.

101002020021 is a deficient number, since it is larger than the sum of its proper divisors (65731473451).

101002020021 is a wasteful number, since it uses less digits than its factorization.

101002020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1603206680 (or 1603206677 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 101002020021 its reverse (120020200101), we get a palindrome (221022220122).

The spelling of 101002020021 in words is "one hundred one billion, two million, twenty thousand, twenty-one".