2102015021 has 2 divisors, whose sum is σ = 2102015022. Its totient is φ = 2102015020.

The previous prime is 2102014991. The next prime is 2102015059. The reversal of 2102015021 is 1205102012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1856748100 + 245266921 = 43090^2 + 15661^2 .

It is a cyclic number.

It is not a de Polignac number, because 2102015021 - 2²² = 2097820717 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2102014987 and 2102015005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2102015081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1051007510 + 1051007511.

It is an arithmetic number, because the mean of its divisors is an integer number (1051007511).

Almost surely, 2^2102015021 is an apocalyptic number.

It is an amenable number.

2102015021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2102015021 is an equidigital number, since it uses as much as digits as its factorization.

2102015021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40, while the sum is 14.

The square root of 2102015021 is about 45847.7373596560. The cubic root of 2102015021 is about 1280.9886203882.

Adding to 2102015021 its reverse (1205102012), we get a palindrome (3307117033).

The spelling of 2102015021 in words is "two billion, one hundred two million, fifteen thousand, twenty-one".