2125454021 has 4 divisors (see below), whose sum is σ = 2132377632. Its totient is φ = 2118530412.

The previous prime is 2125454003. The next prime is 2125454027. The reversal of 2125454021 is 1204545212.

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-2125454021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2125454027) 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, 3461345 + ... + 3461958.

It is an arithmetic number, because the mean of its divisors is an integer number (533094408).

Almost surely, 2^2125454021 is an apocalyptic number.

It is an amenable number.

2125454021 is a deficient number, since it is larger than the sum of its proper divisors (6923611).

2125454021 is an equidigital number, since it uses as much as digits as its factorization.

2125454021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6923610.

The product of its (nonzero) digits is 3200, while the sum is 26.

The square root of 2125454021 is about 46102.6465726210. The cubic root of 2125454021 is about 1285.7323508355.

Adding to 2125454021 its reverse (1204545212), we get a palindrome (3329999233).

The spelling of 2125454021 in words is "two billion, one hundred twenty-five million, four hundred fifty-four thousand, twenty-one".