2103554021 has 4 divisors (see below), whose sum is σ = 2103654252. Its totient is φ = 2103453792.

The previous prime is 2103554017. The next prime is 2103554029. The reversal of 2103554021 is 1204553012.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 744525796 + 1359028225 = 27286^2 + 36865^2 .

It is a cyclic number.

It is not a de Polignac number, because 2103554021 - 2² = 2103554017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2103554029) 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, 5240 + ... + 65073.

It is an arithmetic number, because the mean of its divisors is an integer number (525913563).

Almost surely, 2^2103554021 is an apocalyptic number.

It is an amenable number.

2103554021 is a deficient number, since it is larger than the sum of its proper divisors (100231).

2103554021 is an equidigital number, since it uses as much as digits as its factorization.

2103554021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100230.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 2103554021 is about 45864.5181049578. The cubic root of 2103554021 is about 1281.3011713657.

The spelling of 2103554021 in words is "two billion, one hundred three million, five hundred fifty-four thousand, twenty-one".