2102012021 has 4 divisors (see below), whose sum is σ = 2193403872. Its totient is φ = 2010620172.

The previous prime is 2102011981. The next prime is 2102012027. The reversal of 2102012021 is 1202102012.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2102012021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2102011993 and 2102012011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2102012027) 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, 45695891 + ... + 45695936.

It is an arithmetic number, because the mean of its divisors is an integer number (548350968).

Almost surely, 2^2102012021 is an apocalyptic number.

It is an amenable number.

2102012021 is a deficient number, since it is larger than the sum of its proper divisors (91391851).

2102012021 is an equidigital number, since it uses as much as digits as its factorization.

2102012021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91391850.

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

The square root of 2102012021 is about 45847.7046426536. The cubic root of 2102012021 is about 1280.9880109780.

Adding to 2102012021 its reverse (1202102012), we get a palindrome (3304114033).

The spelling of 2102012021 in words is "two billion, one hundred two million, twelve thousand, twenty-one".