102210020021 has 4 divisors (see below), whose sum is σ = 105734503500. Its totient is φ = 98685536544.

The previous prime is 102210019991. The next prime is 102210020083. The reversal of 102210020021 is 120020012201.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 69018645796 + 33191374225 = 262714^2 + 182185^2 .

It is not a de Polignac number, because 102210020021 - 2⁶ = 102210019957 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 102210019984 and 102210020011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102210020921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1762241696 + ... + 1762241753.

It is an arithmetic number, because the mean of its divisors is an integer number (26433625875).

Almost surely, 2^102210020021 is an apocalyptic number.

It is an amenable number.

102210020021 is a deficient number, since it is larger than the sum of its proper divisors (3524483479).

102210020021 is an equidigital number, since it uses as much as digits as its factorization.

102210020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3524483478.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 102210020021 its reverse (120020012201), we get a palindrome (222230032222).

The spelling of 102210020021 in words is "one hundred two billion, two hundred ten million, twenty thousand, twenty-one".